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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)
guessed Create a notification for this product.
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    "suse_vex": {
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      "current_release_date": "2026-09-10T01:50:45Z",
      "cve": "CVE-2026-80843",
      "id": "CVE-2026-80843",
      "initial_release_date": "2026-09-08T23:58:07Z",
      "product_status:known_affected": "341",
      "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": "3"
    }
  }
}



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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.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • 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.