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CVE-2026-80843 (GCVE-0-2026-80843)

Vulnerability from cvelistv5 – Published: 2026-09-04 15:54 – Updated: 2026-09-04 15:54
VLAI
Title
xfrm: fix xfrm_state_construct() auth-trunc leak
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm: fix xfrm_state_construct() auth-trunc leak attach_auth_trunc() can allocate x->aalg while leaving x->props.aalgo at zero when the selected auth algorithm has no sadb_alg_id. One real case is cmac(aes). xfrm_state_construct() then treats !x->props.aalgo as "no auth algorithm attached yet" and calls attach_auth(). That overwrites x->aalg and loses the first allocation. Any later failure or teardown only frees the replacement pointer. Check whether x->aalg is already attached instead of inferring that state from x->props.aalgo.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < 958ae9f261319e1cdc44879886bcda2263258cca (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < fb7f3e74789a3c89647f4eb768f6dfaf4a751e72 (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < ba0c110c205855b3f1e3130d8c0fdb484d704c8c (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < c8837bbe792257af547fd1c0252553ce13148795 (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < 71d42da01740ec6557837bebec0bc48cfc3b4c39 (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < cf67361e78dca488d6e4df8396a53e6745a3a80e (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < 37426395cb90ef217beec8407a14bd82153793d3 (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < be19d20e53a239572bb2a28efcc1cd2b069b1ef9 (git)
Affected: 4447bb33f09444920a8f1d89e1540137429351b6 , < c12cbf56320fb633484ee0ca1fb7d68d6b64b213 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.33
Unaffected: 0 , < 2.6.33 (semver)
Unaffected: 5.10.269 , ≤ 5.10.* (semver)
Unaffected: 5.15.220 , ≤ 5.15.* (semver)
Unaffected: 6.1.187 , ≤ 6.1.* (semver)
Unaffected: 6.6.156 , ≤ 6.6.* (semver)
Unaffected: 6.12.108 , ≤ 6.12.* (semver)
Unaffected: 6.18.49 , ≤ 6.18.* (semver)
Unaffected: 7.1.13 , ≤ 7.1.* (semver)
Unaffected: 7.2.3 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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        "vulnStatus": "Received"
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      "current_release_date": "2026-09-15T01:07:25Z",
      "cve": "CVE-2026-80843",
      "id": "CVE-2026-80843",
      "initial_release_date": "2026-09-08T23:58:07Z",
      "product_status:known_affected": "353",
      "product_status:recommended": "4",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-80843",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-80843.json",
      "version": "4"
    }
  }
}



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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.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


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.