CVE-2026-39820 (GCVE-0-2026-39820)
Vulnerability from cvelistv5 – Published: 2026-05-07 19:41 – Updated: 2026-05-08 14:27
VLAI?
Title
Quadratic string concatentation in consumeComment in net/mail
Summary
Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
Severity ?
7.5 (High)
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Go standard library | net/mail |
Affected:
0 , < 1.25.10
(semver)
Affected: 1.26.0-0 , < 1.26.3 (semver) |
Credits
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"name": "addrParser.consumeComment"
},
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},
{
"name": "AddressParser.ParseList"
},
{
"name": "Header.AddressList"
},
{
"name": "Header.Date"
},
{
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}
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},
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"url": "https://pkg.go.dev/vuln/GO-2026-4986"
}
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"vulnrichment": {
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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.
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