CVE-2026-72321

UNRATEDCVSS · not yet scoredTrending — 5 sources updated this week
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EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS v2: —Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

ipv4: igmp: Fix potential memory leaks in igmp_mod_timer() and igmp_stop_timer()

When a timer is deleted and not re-armed in igmp_mod_timer(), or stopped in igmp_stop_timer(), the code currently decrements the reference counter of the multicast list entry @im using refcount_dec(&im->refcnt).

However, both functions can be called from the RCU reader path:

  • igmp_mod_timer() via igmp_heard_query() -> for_each_pmc_rcu()
  • igmp_stop_timer() via igmp_rcv() -> igmp_heard_report()

If the group im was concurrently removed from the list by ip_mc_dec_group(), its reference count might have already been decremented to 1.

In this case, timer_delete() succeeds, and refcount_dec() decrements the refcount from 1 to 0. Since refcount_dec() does not free the object when it hits 0 (unlike ip_ma_put()), the im structure is leaked.

Fix this by using ip_ma_put(im) instead of refcount_dec(&im->refcnt), and deferring the put until after the spinlock is released.

CVSS v3
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EchelonGraph score
Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
EG Score
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EG Risk
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EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

August 15, 2026

Last Modified

August 17, 2026

References (3)

Vendor Advisories for CVE-2026-72321(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Data Freshness Timeline

(refreshed 18× in last 7d / 18× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 22:56 UTCEPSS rescore
  2. 2026-08-20 00:34 UTCGHSA enrichment
  3. 2026-08-19 17:04 UTCEPSS rescore
  4. 2026-08-18 13:49 UTCEPSS rescore
  5. 2026-08-18 13:49 UTCEPSS rescore
  6. 2026-08-17 13:47 UTCEPSS rescore
  7. 2026-08-17 06:30 UTCGHSA enrichment
  8. 2026-08-17 06:22 UTCNVD update
  9. 2026-08-17 05:30 UTCEG score recompute
  10. 2026-08-17 05:30 UTCGHSA enrichment
  11. 2026-08-17 05:25 UTCMITRE cvelistV5
  12. 2026-08-16 14:56 UTCEPSS rescore
  13. 2026-08-16 14:56 UTCEPSS rescore
  14. 2026-08-16 02:15 UTCEPSS rescore
  15. 2026-08-15 06:37 UTCGHSA enrichment
  16. 2026-08-15 06:23 UTCNVD update
  17. 2026-08-15 06:07 UTCEG score recompute
  18. 2026-08-15 06:02 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-72321?
CVE-2026-72321 is a publicly disclosed vulnerability published on August 15, 2026. In the Linux kernel, the following vulnerability has been resolved: ipv4: igmp: Fix potential memory leaks in igmpmodtimer() and igmpstoptimer() When a timer is deleted and not re-armed in igmpmodtimer(), or stopped in igmpstoptimer(), the code currently decrements the reference counter of the…
When was CVE-2026-72321 disclosed?
CVE-2026-72321 was first published in the National Vulnerability Database on August 15, 2026, with the most recent update on August 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-72321 actively exploited?
CVE-2026-72321 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 88.9% of all scored CVEs.
How do I remediate CVE-2026-72321?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-72321, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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