CVE-2026-45185
CVE-2026-45185 Vulnerability Analysis & Exploit Intelligence
Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing path. It is triggered when a client sends a TLS close_notify mid-body during a CHUNKING transfer, followed by a final cleartext byte on the same TCP connection. This can lead to heap corruption. An unauthenticated network attacker exploiting this vulnerability could execute arbitrary code.
Published Updated Sources: cvelistV5, mitre
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Exploit code
public exploit, none observed
EPSS
1%
chance of exploitation in 30 days
CVSS base
9.8
CRITICAL
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script all four kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 9.8 | CVSS 3.1 | CRITICAL | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-416
Public exploit
Capability, not use: code existing is a different claim from anyone running it.
Indexed by
References
8 on the record
- exim.org
reference
- code.exim.org/exim/wiki/wiki/EximSecurity
reference
- exim.org/static/doc/security/CVE-2026-45185.txt
reference
- xbow.com/blog/dead-letter-cve-2026-45185-xbow-found-rce-exim
reference
- news.ycombinator.com/item?id=48111748
reference
- www.openwall.com/lists/oss-security/2026/05/12/4
reference
- exim.org/static/doc/security/EXIM-Security-2026-05-01.1/
reference
- www.openwall.com/lists/oss-security/2026/05/12/25
reference
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.