CVE detail
CVE-2026-42530
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.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 24.0 · diversity 20.0 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 1
- within the 30d window
- Peak daily
- 1
- highest bucket
Evidence
Source links by recency
10 source links · newest first
emote crashes in HTTP/2 and HTTP/3 stacks. Three weeks earlier, THN reported a use-after-free in NGINX's HTTP/3 module (CVE-2026-42530) that a remote, unauthenticated client could reach through the same QPACK encoder stream XRING abuses, a different bug class on the same attack surface. In June, Calif's HTTP/2 Bomb caused remote denial of service again
newsthehackernews.comJul 10, 2026, 11:47 AMF5 released emergency updates for critical NGINX flaws (CVE-2026-42530, CVE-2026-42055) that could enable unauthenticated code execution. F5 has issued out-of-band patches for multiple NGINX vulnerabilities, including two critical flaws, respectively tracked as CVE-2026-42530 and CVE-2026-42055 (CVSS 9.2). The bugs affect HTTP modules and can be exploited remotely without authentication to trigger memory corruption, potentially causing […]
newssecurityaffairs.comJun 18, 2026, 2:07 PMLinked URL: https://my.f5.com/manage/s/article/K000161616 | Posted by kro | 7 points | 4 comments
communitynews.ycombinator.comJun 18, 2026, 1:04 PMCritical flaws in NGINX could allow remote, unauthenticated attackers to cause a restart and potentially execute arbitrary code.
newswww.securityweek.comJun 18, 2026, 9:39 AMLinked URL: https://www.cve.org/CVERecord?id=CVE-2026-42530 | Posted by petecooper | 5 points | 2 comments
communitynews.ycombinator.comJun 17, 2026, 4:56 PM- https://access.redhat.com/errata/RHSA-2026:20351access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comJun 17, 2026, 3:16 PM - https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42530.jsonsecurity.access.redhat.com
No excerpt available.
Vendor Advisorysecurity.access.redhat.comJun 17, 2026, 3:16 PM - https://bugzilla.redhat.com/show_bug.cgi?id=2489872bugzilla.redhat.com
No excerpt available.
Exploitbugzilla.redhat.comJun 17, 2026, 3:16 PM - https://access.redhat.com/security/cve/CVE-2026-42530access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comJun 17, 2026, 3:16 PM No excerpt available.
Vendor Advisorymy.f5.comJun 17, 2026, 3:16 PM
Exploit code
Public exploit repository references
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0 repository references · best confidence N/A · max 0 stars
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