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CVE-2026-72068 (GCVE-0-2026-72068)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:52 – Updated: 2026-08-17 05:07
VLAI
Title
posix-cpu-timers: Use u64 multiplication in update_rlimit_cpu()
Summary
In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: Use u64 multiplication in update_rlimit_cpu() update_rlimit_cpu() converts the RLIMIT_CPU value to nanoseconds with u64 nsecs = rlim_new * NSEC_PER_SEC; On 32-bit kernels both rlim_new (unsigned long) and NSEC_PER_SEC (1000000000L) are 32-bit, so the multiplication is performed in unsigned long and truncated for rlim_new > 4 seconds before being widened to u64. The same file already casts to u64 for the matching computation in check_process_timers(): u64 softns = (u64)soft * NSEC_PER_SEC; As a result, the truncated value is installed into the CPUCLOCK_PROF expiry cache (nextevt), causing the process CPU timer to be programmed to fire prematurely for any RLIMIT_CPU soft limit >= 5 seconds. The actual SIGXCPU/SIGKILL decision in check_process_timers() already casts to u64 and is therefore correct, so limit enforcement is not broken; only the expiry-cache programming is wrong. Apply the same cast here so both paths convert rlim_cur identically. 64-bit kernels are unaffected.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < feb5c87c8514444ba891b75a5a3eae57c64edaf8 (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < 384628d6cdde0fcd76868606fad3ad8293100afb (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < 1fafc4d9b411645eb34de43362b966dc8fb3e263 (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < cff8281bacd2866767e6194c3079d33b6c5a74f4 (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < edf6babb9edd2d3e19229ade339081f439d4f478 (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < ea6a188ee805e841a0e242f14d15953e0dfa74bb (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < 571e1f10b5996ba3e4dc63ea77de4aa309c384ce (git)
Affected: 858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4 , < 26aff38fefb1d6cd87e22525f41cc8f1aa61b24f (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.11
Unaffected: 0 , < 4.11 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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              "versionType": "original_commit_for_fix"
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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    "datePublished": "2026-08-15T05:52:21.007Z",
    "dateReserved": "2026-08-09T03:40:39.903Z",
    "dateUpdated": "2026-08-17T05:07:35.943Z",
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      "date": "2026-09-04",
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The\\nactual SIGXCPU/SIGKILL decision in check_process_timers() already casts\\nto u64 and is therefore correct, so limit enforcement is not broken;\\nonly the expiry-cache programming is wrong. Apply the same cast here so\\nboth paths convert rlim_cur identically.\\n\\n64-bit kernels are unaffected.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"kernel/time/posix-cpu-timers.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"feb5c87c8514444ba891b75a5a3eae57c64edaf8\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"384628d6cdde0fcd76868606fad3ad8293100afb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"1fafc4d9b411645eb34de43362b966dc8fb3e263\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"cff8281bacd2866767e6194c3079d33b6c5a74f4\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"edf6babb9edd2d3e19229ade339081f439d4f478\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"ea6a188ee805e841a0e242f14d15953e0dfa74bb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"571e1f10b5996ba3e4dc63ea77de4aa309c384ce\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"858cf3a8c59968e7c5f7c1a1192459a0d52d1ab4\",\"lessThan\":\"26aff38fefb1d6cd87e22525f41cc8f1aa61b24f\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"kernel/time/posix-cpu-timers.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.11\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.11\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.261\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.97\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.5\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/1fafc4d9b411645eb34de43362b966dc8fb3e263\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/26aff38fefb1d6cd87e22525f41cc8f1aa61b24f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/384628d6cdde0fcd76868606fad3ad8293100afb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/571e1f10b5996ba3e4dc63ea77de4aa309c384ce\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/cff8281bacd2866767e6194c3079d33b6c5a74f4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ea6a188ee805e841a0e242f14d15953e0dfa74bb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/edf6babb9edd2d3e19229ade339081f439d4f478\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/feb5c87c8514444ba891b75a5a3eae57c64edaf8\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-08-19T05:25:27+00:00",
      "cve": "CVE-2026-72068",
      "id": "CVE-2026-72068",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "232",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: posix-cpu-timers: Use u64 multiplication in update_rlimit_cpu()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-72068.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.

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.
  • 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.