CVE-2026-56852 (GCVE-0-2026-56852)

Vulnerability from cvelistv5 – Published: 2026-07-21 19:18 – Updated: 2026-08-10 22:57
VLAI
Title
Infinite loop on invalid input in golang.org/x/text
Summary
A norm.Iter can enter an infinite loop when handling input containing invalid UTF-8 bytes.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-23 13:26 UTC
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
Go
References
Impacted products
Vendor Product Version CPE status
golang.org/x/text golang.org/x/text/unicode/norm Affected: 0 , < 0.39.0 (semver)
guessed Create a notification for this product.
Credits
Viky Choi ("vikychoi" on GitHub)
Show details on NVD website
To clipboard 

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              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
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              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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                "timestamp": "2026-07-23T13:26:14.918983Z",
                "version": "2.0.3"
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              "name": "Iter.Next"
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            {
              "name": "Iter.Seek"
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      "product_status:known_not_affected": "4",
      "product_status:under_investigation": "2",
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      "title": "Infinite loop on invalid input in golang.org/x/text",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-56852.json",
      "version": "2"
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}



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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.


Detection rules are retrieved from Rulezet.