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 23 Oct 2026.
The flaw is a heap buffer overflow in the VP8 encoding code of libvpx, the VP8/VP9 video codec library bundled with Google Chrome. An attacker who can get a victim to load a crafted HTML page can potentially corrupt heap memory, with no authentication or additional configuration required beyond the victim's browser user interaction.
Official description · NVDSource 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 NVD.
Heap buffer overflow in vp8 encoding in libvpx in Google Chrome prior to 117.0.5938.132 and libvpx 1.13.1 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
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
68.9 / 100
Exploited
Yes, in CISA KEV
Reports
0
Tactics
2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.
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.
First seen exploited 3 days before it was disclosed. Public exploit code (PoC-in-GitHub) appeared 8 days after disclosure.
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
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.
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
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain orderSourceSource 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.2
Source 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. CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Buffer Overflow.MITRE CTID mapping of the KEV entry · how it is exploited
This vulnerability was exploited by a remote attacker using a crafted HTML page to trigger a heap buffer overflow in the vp8 encoding of libvpx, leading to heap corruption. This flaw was part of a spyware campaign. The exploitation allowed for program crashes or arbitrary code execution, ultimately resulting in the installation of spyware.
Source 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. CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Buffer Overflow.MITRE CTID mapping of the KEV entry · primary impact
Detection
0 rules for this CVE · 12 general rules for its techniques
Rules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2023-5217 directly.
CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
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.