CVE-2026-74735 (GCVE-0-2026-74735)

Vulnerability from cvelistv5 – Published: 2026-08-26 14:36 – Updated: 2026-10-30 12:30
VLAI
Title
l2tp: fix tunnel and session refcount leak on seq_file release
Summary
In the Linux kernel, the following vulnerability has been resolved: l2tp: fix tunnel and session refcount leak on seq_file release In pppol2tp_proc_open() and l2tp_dfs_seq_open(), iteration state (pd->tunnel and pd->session) is kept in seq_file private data to allow iteration across multiple read() system calls. However, if userspace closes /proc/net/pppol2tp or /sys/kernel/debug/l2tp/tunnels before reading to end-of-file (EOF), any tunnel or session reference stored in pd->tunnel / pd->session is left un-dropped when seq_file private data is freed. Fix this by dropping any remaining pd->tunnel and pd->session references in pppol2tp_proc_release() and l2tp_dfs_seq_release() when closing the file.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6641 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < c38b723858a51d6ca4e56470b9f1087f23276772 (git)
Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < bd897e414451fb34dfdf08b31899180e5ab7149b (git)
Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < bdf83613781956cc39798ed08321f74ab0467f4d (git)
Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < 8c4fde01bcf91f22b9c7ded8c3e14addd7ddd500 (git)
Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < ebe2774e956482dd3c70b8991f6f7654356339e6 (git)
Affected: 0e0c3fee3a59a387aeecc4fca6f3a2e9615a5443 , < 9006c116dd111d457bf5d074990210f70a4ad2c8 (git)
Affected: f6104e9ae04462523c372928b1173766a771ef95 (git)
Affected: 7f8e401f9e612df2a95c1ef76217c00181389bb5 (git)
Affected: c712ed63e9b33d9a282fbd92ce25c64918c3129f (git)
Affected: 9a8863e8a8def9d88583cd9c60db38a008e6b8cf (git)
Affected: 3.16.60 , < 3.17 (semver)
Affected: 4.16.6 , < 4.17 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 4.17
Unaffected: 0 , < 4.17 (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.111 , ≤ 6.12.* (semver)
Unaffected: 6.18.53 , ≤ 6.18.* (semver)
Unaffected: 7.1.10 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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      "cve": "CVE-2026-74735",
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      "product_status:known_affected": "158",
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      "source": "Red Hat CSAF VEX",
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      "title": "kernel: l2tp: fix tunnel and session refcount leak on seq_file release",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74735.json",
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      "current_release_date": "2026-11-11T02:01:37Z",
      "cve": "CVE-2026-74735",
      "id": "CVE-2026-74735",
      "initial_release_date": "2026-08-27T00:21:34Z",
      "product_status:known_affected": "677",
      "product_status:known_not_affected": "39",
      "product_status:recommended": "252",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74735",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2026/cve-2026-74735.json",
      "version": "14"
    }
  }
}



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    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.