CVE-2019-16928
Memory Safety in Fedoraproject Fedora 29 … 31
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2019-16928 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Fedoraproject Fedora. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Exim versions 4.92 through 4.92.2 contain a heap-based buffer overflow in the string_vformat function within string.c. The flaw is triggered by an overly long EHLO command and is distinct from the separate issue tracked as CVE-2019-15846. It is assigned CWE-787 and carries a CVSS 3.1 base score of 9.8, reflecting network attack vector, low complexity, and no required privileges or user interaction.
An unauthenticated remote attacker can send a crafted EHLO command to an affected Exim server and achieve arbitrary code execution with full impact on confidentiality, integrity, and availability. The vulnerability is exploitable over the network without any authentication or special conditions.
Public advisories and technical details, including potential mitigation steps and patch information, are discussed in the referenced Openwall mailing-list posts and the Exim bug tracker entry at https://bugs.exim.org/show_bug.cgi?id=2449. No information on observed in-the-wild exploitation is provided in the available references.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2019-7422
Vulnerability Data
Exim 4.92 through 4.92.2 allows remote code execution, a different vulnerability than CVE-2019-15846. There is a heap-based buffer overflow in string_vformat in string.c involving a long EHLO command.
- CWE(s)
- KEV Date Added
- 03 March 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.
Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.
Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.