Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate sig

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• mercurial mercurialbefore 1.6.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (canonical). Independent of NVD's CPE analysis and usually ahead of it.

• mercurial mercurial

  • 1.6.4affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2014-9390Git before 1.8.5.6, 1.9.x before 1.9.5, 2.0.x before 2.0.5, 2.1.x before 2.1.4, and 2.2.x before 2.2.1 on Windows and OS X; Mercurial before
  62This week
• CVE-2017-9462In Mercurial before 4.1.3, "hg serve --stdio" allows remote authenticated users to launch the Python debugger, and consequently execute arbi
  42Plan
• CVE-2017-17458In Mercurial before 4.4.1, it is possible that a specially malformed repository can cause Git subrepositories to run arbitrary code in the f
  41Plan
• CVE-2017-1000116Mercurial prior to 4.3 did not adequately sanitize hostnames passed to ssh, leading to possible shell-injection attacks.
  41Plan
• CVE-2018-13347mpatch.c in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.
  40Plan
• CVE-2018-17983cext/manifest.c in Mercurial before 4.7.2 has an out-of-bounds read during parsing of a malformed manifest entry.
  37Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {2  // Left empty for the test environment3}

1val client = OkHttpClient.Builder()2  .certificatePinner(3    CertificatePinner.Builder()4      .add("api.sirius.example", "sha256/…")5      .build()6  ).build()

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.