by Kastro
Paper/Archive/CVE-2026-85181

CVE-2026-85181

dianping cat — CAT through 3.1.0 Session Cookie Forgery via Unkeyed hashCode Checksum

EPSS 0.7%CVSS 9.8
critical.is priorityof 100
40
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 53.4.534 × 2010.7No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

CAT uses Java String.hashCode as the sole integrity check for session cookies without server-side keying, allowing attackers to forge valid checksums offline. Attackers can set the x-forwarded-for header to bypass IP binding validation and create admin sessions with full configuration access.

Affected

ProductAffectedFixed inSource
cat≤ 3.1.0–CNA

Scores by source

VulnCheck (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/dianping/cat/issues/2384refgithub.com/dianping/catwriteupgithub.com/dianping/cat/blob/3.1.0/cat-home/src/main/java/com/dianping/cat/system/page/login/service/TokenBuilder.javawriteupgithub.com/dianping/cat/blob/3.1.0/cat-home/src/main/java/com/dianping/cat/util/HttpUtils.javawriteupvulncheck.com/advisories/cat-through-3.1.0-session-cookie-forgery-via-unkeyed-hashcode-checksum