Uncontrolled Recursion in Apache bRPC - CVE-2026-54425
Published: October 23, 2026
Vulnerability identifier: #VU157337
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-54425
CWE-ID: CWE-674
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service by exhausting the thread stack.
The vulnerability exists due to uncontrolled recursion in Apache bRPC's HTTP/2 HPACK decoder when processing consecutive Dynamic Table Size Update entries. A remote attacker can send a crafted HTTP/2 header block containing many such entries to trigger unbounded recursive decoding and exhaust the thread stack.
Affected software
Apache bRPC
How to mitigate CVE-2026-54425
Install security update from vendor's website.
Apache bRPC - update to 1.18.0