CVE-2026-42530

high

Published 2026-06-17 · Modified 2026-06-17

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CVSS v3

8.1

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v4 NEW

9.2

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

VIR risk

8.1

Description

NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Predictions

Exploit likelihood

88%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

https://my.f5.com/manage/s/article/K000161616

CWEs

CWE-416

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.