CVE-2013-2551
CVE-2013-2551 is a security flaw in Microsoft Internet Explorer, Microsoft’s old web browser, still built into Windows. Attackers can run their own code on Microsoft Internet Explorer. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 28 Mar 2022, and says ransomware gangs have used it.[1]
Microsoft Internet Explorer is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Microsoft has published a fix or advice.
Description
CISA calls it an use-after-free in Microsoft Internet Explorer. In its words: “Use-after-free vulnerability in Microsoft Internet Explorer allows remote attackers to execute remote code via a crafted web site that triggers access to a deleted object.”[1]
The CVE record adds: “Use-after-free vulnerability in Microsoft Internet Explorer 6 through 10 allows remote attackers to execute arbitrary code via a crafted web site that triggers access to a deleted object, as demonstrated by VUPEN during a Pwn2Own competition at CanSecWest 2013, aka "Internet Explorer Use After Free Vulnerability," a different vulnerability than CVE-2013-1308 and CVE-2013-1309.”[2]
The underlying weakness is use after free (CWE-416), in MITRE’s list of common software weaknesses.
It scores 8.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Microsoft’s advisory has them[3]. CISA names the product as Microsoft Internet Explorer.
Every device with Microsoft Internet Explorer needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 28 Mar 2022, 3,304 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 18 Apr 2022 to fix it.[1] CISA says ransomware gangs have used it.
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 74%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Microsoft has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Update Microsoft Internet Explorer now.Install the latest update from Microsoft on every device that has it, and restart when asked. Then turn on automatic updates, so the next fix arrives on its own.
- If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 8.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks, noting that ransomware gangs have used it.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 74%.[4] |
See also
Other Microsoft Internet Explorer flaws
- CVE-2010-0806: use-after-free ·
- CVE-2010-0249: use-after-free ·
- CVE-2010-3962: uninitialized memory corruption ·
- CVE-2013-3893: resource management errors ·
- CVE-2012-4792: use-after-free ·
- CVE-2013-3163: memory corruption ·
Other Microsoft flaws
- CVE-2026-96951, Microsoft Windows: command injection ·
- CVE-2026-65660, Microsoft SharePoint: code injection ·
- CVE-2026-85880, Microsoft Windows: heap-based buffer overflow ·
- CVE-2026-81963, Microsoft Windows: link following ·
- CVE-2019-1068, Microsoft SQL Server: remote code execution ·
Other use after free flaws
- CVE-2026-109619, PHP: stale internal request-state ·
- CVE-2026-109618, PHP: memory corruption ·
- CVE-2020-9715, Adobe Acrobat: use-after-free ·
- CVE-2026-5281, Google Dawn: use-after-free ·
- CVE-2023-43000, Apple devices: use-after-free ·
Added the same day
- CVE-2022-1096, Chrome and other Chromium browsers: type confusion ·
- CVE-2022-0543, Redis Debian-specific Redis Servers: debian-specific redis server lua sandbox escape ·
- CVE-2021-38646, Microsoft Office: access connectivity engine remote code execution ·
- CVE-2021-34486, Microsoft Windows: event tracing privilege escalation ·
- CVE-2021-26085, Atlassian Confluence Server: pre-authorization arbitrary file read ·
Every Microsoft flaw on CISA’s list · Everything added in March 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “Microsoft Internet Explorer Use-After-Free Vulnerability”. Known Exploited Vulnerabilities Catalog, added 28 Mar 2022.
- ^ National Institute of Standards and Technology. “CVE-2013-2551 Detail”. National Vulnerability Database, published 11 Mar 2013.
- ^ Microsoft. Advisories and fixes: docs.microsoft.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.739, percentile 99.5, 31 Oct 2026.
- CVE Program. “CVE-2013-2551”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.