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

Vulnerability from cvelistv5 – Published: 2026-08-26 14:36 – Updated: 2026-08-26 14:36
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
References
Impacted products
Vendor Product Version CPE status
Linux Linux 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)
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Linux Linux Affected: 4.17
Unaffected: 0 , < 4.17 (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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    "datePublished": "2026-08-26T14:36:49.352Z",
    "dateReserved": "2026-08-15T05:44:03.930Z",
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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

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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.
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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.


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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.