Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Network-reachable and pre-authentication (AV:N/PR:N), but AC:H because it needs the GnuTLS backend plus non-default TLS settings; use-after-free yields a crash so A:L, C/I:N.
Primary rating from Vendor (mitre).
CVSS VectorVendor: mitre
Lifecycle Timeline
3DescriptionCVE.org
Exim before 4.100.1, when certain non-default TLS settings are used with GnuTLS, has a use-after-free.
AnalysisAI
A use-after-free memory-safety flaw in Exim before 4.100.1 can crash the mail transfer agent process when the daemon is compiled against the GnuTLS TLS backend and configured with certain non-default TLS settings; once a vulnerable server is reachable over the network, no authentication (PR:N) or user interaction (UI:N) is required, but the CVSS vector reflects high attack complexity (AC:H) because the triggering configuration is unusual and non-default. The assessed impact is availability-only (C:N/I:N/A:L) - a crash or degraded service rather than code execution or data exposure. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires Exim (before 4.100.1) built against the GnuTLS TLS library AND configured with certain non-default TLS settings - the flaw does not affect the OpenSSL backend or default TLS configurations. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | This is a genuinely low-priority issue despite affecting an extremely widely-deployed product. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Full exploit scenario with step-by-step reproduction available after sign-in. |
| Remediation | The primary fix is to upgrade Exim to version 4.100.1 or later, the first release in which this use-after-free is addressed; see the vendor advisory at https://lists.exim.org/lurker/message/20260918.121220.0f87338e.en.html for the exact fixed build and any packaging guidance. … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to execute arbitr
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to cause a denial
Exim before 4.86.2, when installed setuid root, allows local users to gain privileges via the perl_startup argument. Rat
Exim mail server version 4.98 before 4.98.1 contains a remote SQL injection vulnerability when SQLite hints and ETRN ser
A flaw was found in Exim versions 4.87 to 4.91 (inclusive). Rated critical severity (CVSS 9.8), this vulnerability is re
Heap-based buffer overflow in the dkim_exim_query_dns_txt function in dkim.c in Exim 4.70 through 4.80, when DKIM suppor
Exim before 4.95 has a heap-based buffer overflow for the alias list in host_name_lookup in host.c when sender_host_name
Exim 4.92 through 4.92.2 allows remote code execution, a different vulnerability than CVE-2019-15846. Rated critical sev
An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. Rated critical severity (CVS
A UNIX Symbolic Link (Symlink) Following vulnerability in the packaging of exim in openSUSE Factory allows local attacke
Exim before 4.96 has an invalid free in pam_converse in auths/call_pam.c because store_free is not used after store_mall
Exim through 4.93 has an out-of-bounds read in the SPA authenticator that could result in SPA/NTLM authentication bypass
Same weakness CWE-416 – Use After Free
View allSame technique Information Disclosure
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-83613
GHSA-jpgj-v2p6-hc2c