CVE-2019-11759: An attacker could have caused 4 bytes of HMAC output to be written past the end of a buffer stored on the stack.

Affected versions

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

• canonical ubuntu linux16.04
• mozilla firefoxbefore 70.0
• mozilla firefox esrbefore 68.2
• mozilla thunderbirdbefore 68.2

Versions reported by the vendor

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

• Mozilla Firefox

  • before 70affected

• Mozilla Firefox ESR

  • before 68.2affected

• Mozilla Thunderbird

  • before 68.2affected

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-2010-3765Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before 3.1.6 and 3.0.x before 3.0.10, and SeaMonkey 2.x befKEV
  94Now
• CVE-2019-11708Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxeKEV
  87Now
• CVE-2015-4495The PDF reader in Mozilla Firefox before 39.0.3, Firefox ESR 38.x before 38.1.1, and Firefox OS before 2.2 allows remote attackers to bypassKEV
  86Now

Published before and after this one in the same product

• ← EarlierCVE-2019-11757Jan 8, 2020 · When following the value's prototype chain, it was possible to retain a reference to a locale, delete it, and subsequently reference it.
  35Monitor
• ← EarlierCVE-2019-11758Jan 8, 2020 · Mozilla community member Philipp reported a memory safety bug present in Firefox 68 when 360 Total Security was installed.
  35Monitor
• Later →CVE-2019-11760Jan 8, 2020 · A fixed-size stack buffer could overflow in nrappkit when doing WebRTC signaling.
  35Monitor

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

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

1char buf[256];2memcpy(buf, pkt->data, pkt->len);

1char buf[256];2if (pkt->len > sizeof(buf)) {3  return -EINVAL;4}5memcpy(buf, pkt->data, pkt->len);

Attack context

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