CVE-2026-2903 (GCVE-0-2026-2903)
Vulnerability from cvelistv5 – Published: 2026-02-22 00:32 – Updated: 2026-06-23 15:50 X_Open Source
VLAI
EPSS
VEX
Title
skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference
Summary
A flaw has been found in skvadrik re2c up to 4.4. Impacted is the function check_and_merge_special_rules of the file src/parse/ast.cc. This manipulation causes null pointer dereference. The attack can only be executed locally. The exploit has been published and may be used. Patch name: febeb977936f9519a25d9fbd10ff8256358cdb97. It is suggested to install a patch to address this issue.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-26 16:21 UTC
Assigner
References
8 references
| URL | Tags |
|---|---|
| https://vuldb.com/?id.347210 | vdb-entrytechnical-description |
| https://vuldb.com/?ctiid.347210 | signaturepermissions-required |
| https://vuldb.com/?submit.755030 | third-party-advisory |
| https://github.com/skvadrik/re2c/issues/571 | issue-tracking |
| https://github.com/skvadrik/re2c/issues/571#issue… | issue-tracking |
| https://github.com/oneafter/0202/blob/main/re/repro | exploit |
| https://github.com/skvadrik/re2c/commit/febeb9779… | patch |
| https://github.com/skvadrik/re2c/ | product |
Impacted products
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-2903",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-02-26T16:21:03.435710Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-06-23T15:50:16.004Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"cpes": [
"cpe:2.3:a:re2c:re2c:*:*:*:*:*:*:*:*"
],
"product": "re2c",
"vendor": "skvadrik",
"versions": [
{
"status": "affected",
"version": "4.0"
},
{
"status": "affected",
"version": "4.1"
},
{
"status": "affected",
"version": "4.2"
},
{
"status": "affected",
"version": "4.3"
},
{
"status": "affected",
"version": "4.4"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "Oneafter (VulDB User)"
}
],
"descriptions": [
{
"lang": "en",
"value": "A flaw has been found in skvadrik re2c up to 4.4. Impacted is the function check_and_merge_special_rules of the file src/parse/ast.cc. This manipulation causes null pointer dereference. The attack can only be executed locally. The exploit has been published and may be used. Patch name: febeb977936f9519a25d9fbd10ff8256358cdb97. It is suggested to install a patch to address this issue."
}
],
"metrics": [
{
"cvssV4_0": {
"baseScore": 4.8,
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P",
"version": "4.0"
}
},
{
"cvssV3_1": {
"baseScore": 3.3,
"baseSeverity": "LOW",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C",
"version": "3.1"
}
},
{
"cvssV3_0": {
"baseScore": 3.3,
"baseSeverity": "LOW",
"vectorString": "CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C",
"version": "3.0"
}
},
{
"cvssV2_0": {
"baseScore": 1.7,
"vectorString": "AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:OF/RC:C",
"version": "2.0"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-404",
"description": "Denial of Service",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-02-22T00:32:09.412Z",
"orgId": "1af790b2-7ee1-4545-860a-a788eba489b5",
"shortName": "VulDB"
},
"references": [
{
"name": "VDB-347210 | skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference",
"tags": [
"vdb-entry",
"technical-description"
],
"url": "https://vuldb.com/?id.347210"
},
{
"name": "VDB-347210 | CTI Indicators (IOB, IOC, IOA)",
"tags": [
"signature",
"permissions-required"
],
"url": "https://vuldb.com/?ctiid.347210"
},
{
"name": "Submit #755030 | skvadrik re2c 04f1424 NULL Pointer Dereference",
"tags": [
"third-party-advisory"
],
"url": "https://vuldb.com/?submit.755030"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/skvadrik/re2c/issues/571"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/skvadrik/re2c/issues/571#issuecomment-3837675101"
},
{
"tags": [
"exploit"
],
"url": "https://github.com/oneafter/0202/blob/main/re/repro"
},
{
"tags": [
"patch"
],
"url": "https://github.com/skvadrik/re2c/commit/febeb977936f9519a25d9fbd10ff8256358cdb97"
},
{
"tags": [
"product"
],
"url": "https://github.com/skvadrik/re2c/"
}
],
"tags": [
"x_open-source"
],
"timeline": [
{
"lang": "en",
"time": "2026-02-20T00:00:00.000Z",
"value": "Advisory disclosed"
},
{
"lang": "en",
"time": "2026-02-20T01:00:00.000Z",
"value": "VulDB entry created"
},
{
"lang": "en",
"time": "2026-02-20T21:07:45.000Z",
"value": "VulDB entry last update"
}
],
"title": "skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference"
}
},
"cveMetadata": {
"assignerOrgId": "1af790b2-7ee1-4545-860a-a788eba489b5",
"assignerShortName": "VulDB",
"cveId": "CVE-2026-2903",
"datePublished": "2026-02-22T00:32:09.412Z",
"dateReserved": "2026-02-20T20:02:38.891Z",
"dateUpdated": "2026-06-23T15:50:16.004Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-2903",
"date": "2026-09-28",
"epss": "0.00166",
"percentile": "0.05224"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"cpes": [
"cpe:2.3:a:re2c:re2c:*:*:*:*:*:*:*:*"
],
"product": "re2c",
"vendor": "skvadrik",
"versions": [
{
"status": "affected",
"version": "4.0"
},
{
"status": "affected",
"version": "4.1"
},
{
"status": "affected",
"version": "4.2"
},
{
"status": "affected",
"version": "4.3"
},
{
"status": "affected",
"version": "4.4"
}
]
}
],
"source": "cna@vuldb.com"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A flaw has been found in skvadrik re2c up to 4.4. Impacted is the function check_and_merge_special_rules of the file src/parse/ast.cc. This manipulation causes null pointer dereference. The attack can only be executed locally. The exploit has been published and may be used. Patch name: febeb977936f9519a25d9fbd10ff8256358cdb97. It is suggested to install a patch to address this issue."
},
{
"lang": "es",
"value": "Se ha encontrado una vulnerabilidad en skvadrik re2c hasta la versi\u00f3n 4.4. La funci\u00f3n afectada es check_and_merge_special_rules del archivo src/parse/ast.cc. Esta manipulaci\u00f3n provoca una desreferencia de puntero nulo. El ataque solo puede ejecutarse localmente. El exploit ha sido publicado y puede ser utilizado. Nombre del parche: febeb977936f9519a25d9fbd10ff8256358cdb97. Se sugiere instalar un parche para solucionar este problema."
}
],
"id": "CVE-2026-2903",
"lastModified": "2026-06-17T10:32:00.180",
"metrics": {
"cvssMetricV2": [
{
"acInsufInfo": false,
"baseSeverity": "LOW",
"cvssData": {
"accessComplexity": "LOW",
"accessVector": "LOCAL",
"authentication": "SINGLE",
"availabilityImpact": "PARTIAL",
"baseScore": 1.7,
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"vectorString": "AV:L/AC:L/Au:S/C:N/I:N/A:P",
"version": "2.0"
},
"exploitabilityScore": 3.1,
"impactScore": 2.9,
"obtainAllPrivilege": false,
"obtainOtherPrivilege": false,
"obtainUserPrivilege": false,
"source": "cna@vuldb.com",
"type": "Secondary",
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "LOW",
"baseScore": 3.3,
"baseSeverity": "LOW",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 1.4,
"source": "cna@vuldb.com",
"type": "Secondary"
}
],
"cvssMetricV40": [
{
"cvssData": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "LOCAL",
"availabilityRequirement": "NOT_DEFINED",
"baseScore": 1.9,
"baseSeverity": "LOW",
"confidentialityRequirement": "NOT_DEFINED",
"exploitMaturity": "PROOF_OF_CONCEPT",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"privilegesRequired": "LOW",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"version": "4.0",
"vulnAvailabilityImpact": "LOW",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"source": "cna@vuldb.com",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-2903",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-02-26T16:21:03.435710Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-02-22T01:16:00.563",
"references": [
{
"source": "cna@vuldb.com",
"url": "https://github.com/oneafter/0202/blob/main/re/repro"
},
{
"source": "cna@vuldb.com",
"url": "https://github.com/skvadrik/re2c/"
},
{
"source": "cna@vuldb.com",
"url": "https://github.com/skvadrik/re2c/commit/febeb977936f9519a25d9fbd10ff8256358cdb97"
},
{
"source": "cna@vuldb.com",
"url": "https://github.com/skvadrik/re2c/issues/571"
},
{
"source": "cna@vuldb.com",
"url": "https://github.com/skvadrik/re2c/issues/571#issuecomment-3837675101"
},
{
"source": "cna@vuldb.com",
"url": "https://vuldb.com/?ctiid.347210"
},
{
"source": "cna@vuldb.com",
"url": "https://vuldb.com/?id.347210"
},
{
"source": "cna@vuldb.com",
"url": "https://vuldb.com/?submit.755030"
}
],
"sourceIdentifier": "cna@vuldb.com",
"vulnStatus": "Deferred",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-404"
},
{
"lang": "en",
"value": "CWE-476"
}
],
"source": "cna@vuldb.com",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Low",
"current_release_date": "2026-06-28T12:03:07+00:00",
"cve": "CVE-2026-2903",
"id": "CVE-2026-2903",
"initial_release_date": "2026-02-22T00:32:09.412000+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "re2c: re2c: Denial of Service via null pointer dereference",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2903.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "low",
"current_release_date": "2026-08-28T16:46:49Z",
"cve": "CVE-2026-2903",
"id": "CVE-2026-2903",
"initial_release_date": "2026-02-24T00:24:34Z",
"product_status:known_affected": "3",
"product_status:known_not_affected": "45",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-2903",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-2903.json",
"version": "6"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-2903",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-02-26T16:21:03.435710Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-02-26T16:21:09.494Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"cpes": [
"cpe:2.3:a:re2c:re2c:*:*:*:*:*:*:*:*"
],
"product": "re2c",
"vendor": "skvadrik",
"versions": [
{
"status": "affected",
"version": "4.0"
},
{
"status": "affected",
"version": "4.1"
},
{
"status": "affected",
"version": "4.2"
},
{
"status": "affected",
"version": "4.3"
},
{
"status": "affected",
"version": "4.4"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "Oneafter (VulDB User)"
}
],
"descriptions": [
{
"lang": "en",
"value": "A flaw has been found in skvadrik re2c up to 4.4. Impacted is the function check_and_merge_special_rules of the file src/parse/ast.cc. This manipulation causes null pointer dereference. The attack can only be executed locally. The exploit has been published and may be used. Patch name: febeb977936f9519a25d9fbd10ff8256358cdb97. It is suggested to install a patch to address this issue."
}
],
"metrics": [
{
"cvssV4_0": {
"baseScore": 4.8,
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P",
"version": "4.0"
}
},
{
"cvssV3_1": {
"baseScore": 3.3,
"baseSeverity": "LOW",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C",
"version": "3.1"
}
},
{
"cvssV3_0": {
"baseScore": 3.3,
"baseSeverity": "LOW",
"vectorString": "CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C",
"version": "3.0"
}
},
{
"cvssV2_0": {
"baseScore": 1.7,
"vectorString": "AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:OF/RC:C",
"version": "2.0"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-404",
"description": "Denial of Service",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-02-22T00:32:09.412Z",
"orgId": "1af790b2-7ee1-4545-860a-a788eba489b5",
"shortName": "VulDB"
},
"references": [
{
"name": "VDB-347210 | skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference",
"tags": [
"vdb-entry",
"technical-description"
],
"url": "https://vuldb.com/?id.347210"
},
{
"name": "VDB-347210 | CTI Indicators (IOB, IOC, IOA)",
"tags": [
"signature",
"permissions-required"
],
"url": "https://vuldb.com/?ctiid.347210"
},
{
"name": "Submit #755030 | skvadrik re2c 04f1424 NULL Pointer Dereference",
"tags": [
"third-party-advisory"
],
"url": "https://vuldb.com/?submit.755030"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/skvadrik/re2c/issues/571"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/skvadrik/re2c/issues/571#issuecomment-3837675101"
},
{
"tags": [
"exploit"
],
"url": "https://github.com/oneafter/0202/blob/main/re/repro"
},
{
"tags": [
"patch"
],
"url": "https://github.com/skvadrik/re2c/commit/febeb977936f9519a25d9fbd10ff8256358cdb97"
},
{
"tags": [
"product"
],
"url": "https://github.com/skvadrik/re2c/"
}
],
"tags": [
"x_open-source"
],
"timeline": [
{
"lang": "en",
"time": "2026-02-20T00:00:00.000Z",
"value": "Advisory disclosed"
},
{
"lang": "en",
"time": "2026-02-20T01:00:00.000Z",
"value": "VulDB entry created"
},
{
"lang": "en",
"time": "2026-02-20T21:07:45.000Z",
"value": "VulDB entry last update"
}
],
"title": "skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference"
}
},
"cveMetadata": {
"assignerOrgId": "1af790b2-7ee1-4545-860a-a788eba489b5",
"assignerShortName": "VulDB",
"cveId": "CVE-2026-2903",
"datePublished": "2026-02-22T00:32:09.412Z",
"dateReserved": "2026-02-20T20:02:38.891Z",
"dateUpdated": "2026-06-23T15:50:16.004Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…