SummaryAI-written · claude-haiku-5-5AI-written · claude-haiku-5-5Written by a language model from the source data on this page. Not reviewed by a person. Generated 29 Oct 2026.
The flaw is a buffer overrun in OpenSSL's X.509 certificate verification, specifically in name constraint checking, which lets an attacker overflow four attacker-controlled bytes on the stack using a crafted email address. An attacker can trigger it remotely by connecting a TLS client to a malicious server, or by having a malicious client connect to a TLS server that requests client authentication, and exploitation requires that a CA signed the malicious certificate or that the application continues verification after failing to build a path to a trusted issuer.
Official description · CVE.orgSource dataSource dataCopied from an authoritative feed: NVD, CVE.org, CISA KEV, FIRST EPSS or MITRE CTID mappings, or labelled by the annotators of a published dataset. Copied from CVE.org.
A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the application to continue certificate verification despite failure to construct a path to a trusted issuer. An attacker can craft a malicious email address to overflow four attacker-controlled bytes on the stack. This buffer overflow could result in a crash (causing a denial of service) or potentially remote code execution. Many platforms implement stack overflow protections which would mitigate against the risk of remote code execution. The risk may be further mitigated based on stack layout for any given platform/compiler. Pre-announcements of CVE-2022-3602 described this issue as CRITICAL. Further analysis based on some of the mitigating factors described above have led this to be downgraded to HIGH. Users are still encouraged to upgrade to a new version as soon as possible. In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects. Fixed in OpenSSL 3.0.7 (Affected 3.0.0,3.0.1,3.0.2,3.0.3,3.0.4,3.0.5,3.0.6).
Priority scorePatchfirst’s 0 to 100 ranking. It adds points for CISA KEV listing, ransomware use, EPSS, threat reports, public exploit code and CVSS. Every CVE page shows the breakdown.Breakdown
33.2 / 100
Exploited
Not confirmed
Reports
0
Tactics
0/15
Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
Public exploit code (PoC-in-GitHub) was available 4 days before disclosure.
Patch historyEarlier and later CVEs in the same code, in date order. It shows when a fix was bypassed or incomplete and which version finally fixed it.
7 fixes in openssl-src over 8 months. The latest fix listed for openssl-src is 300.0.12.
Fixes in openssl-srcCargo package, by fixed version. Earlier and later fixes in the same package, not necessarily the same bug.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
No techniques linked
No ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.
Am I affected? What do I upgrade to?
From GitHub Security Advisories and OSVSourceSource dataCopied from an authoritative feed: NVD, CVE.org, CISA KEV, FIRST EPSS or MITRE CTID mappings, or labelled by the annotators of a published dataset. GitHub Security Advisories and OSV.
1 package in 1 ecosystem. Main package: openssl-src.