The EPATHOBJ::pprFlattenRec function in win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, and Windows Server 2012 does not properly initialize a pointer for the next object in a certain list, which allows local users to obtain write access to the PATHRECORD chain, and consequently gain privileges, by triggering excessive consumption of paged memory and then making many FlattenPath function calls, aka "Win32k Read AV Vulnerability."
CVE-2013-3660
“▲” beside the score: it is higher than NVD's CVSS score.
Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2022-03-28), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 7.8 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 7.8 HIGH under GitHub Security Advisory CVSS. Confidence: HIGH.
Also known asEUVD-2013-3593 (ENISA EUVD) · GHSA-f2wh-c6mm-3vrx (GitHub Security Advisories)Source: ENISA EUVD
- Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).
- CVSS v3
- 7.8
- EG Score
- 9.0CRITICALhigh confidence
- EG Risk
- 75EG Risk 75/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity78% × 45%Impact severity (EG Severity): CVSS 7.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation100% × 40%Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Attend at medium and Act at high mission impact.Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low, sooner than that at medium and as soon as possible at high mission impact. - EPSS PROB
- 39%
- EPSS %ILE
- 98th
- KEV
- ⚠ Exploited
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 7.8 HIGH.
- EG Severity
- 7.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 39% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Attend at medium mission impactTrack at low, Attend at medium and Act at high mission impact.CISA BOD 26-04: 3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Attend at medium and Act at high mission impact.
A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low, sooner than that at medium and as soon as possible at high mission impact.
Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.
No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.
The score's inputs: In CISA KEV yes (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
CISA required action“Apply updates per vendor instructions.”
Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://nvd.nist.gov/vuln/detail/CVE-2013-3660
Published
May 24, 2013
Last Modified
April 22, 2026
Advisory Details (3)
Auto-updated Nov 2, 2026Microsoft Windows - Win32k!EPATHOBJ::pprFlattenRec Uninitialized Next Pointer Testcase - Windows dos Exploit
http://www.exploit-db.com/exploits/25611/Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 19× in last 7d / 122× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 100 of 1,057 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 957 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-02 10:52 UTCEG score recompute
- 2026-11-02 10:52 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub severity MODERATE · GitHub CVSS 7.8
- 2026-11-01 09:31 UTCEG score recompute
- 2026-11-01 09:31 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub severity MODERATE · GitHub CVSS 7.8
- 2026-10-31 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-31 08:12 UTCEG score recompute
- 2026-10-31 08:12 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-30 16:27 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-30 06:52 UTCEG score recompute
- 2026-10-30 06:52 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-29 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-29 05:32 UTCEG score recompute
- 2026-10-29 05:32 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-28 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-28 04:13 UTCEG score recompute
- 2026-10-28 04:13 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-27 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-27 02:52 UTCEG score recompute
- 2026-10-27 02:52 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-26 16:25 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-26 01:32 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-25 20:08 UTCEG score recompute
- 2026-10-25 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-25 00:12 UTCEG score recompute
- 2026-10-25 00:12 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
Show 75 moreShow fewer
- 2026-10-23 22:53 UTCEG score recompute
- 2026-10-23 22:53 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-23 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-22 21:33 UTCEG score recompute
- 2026-10-22 21:32 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-22 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-21 20:12 UTCEG score recompute
- 2026-10-21 20:12 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-21 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-20 18:52 UTCEG score recompute
- 2026-10-20 18:52 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-20 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-19 17:33 UTCEG score recompute
- 2026-10-19 17:32 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-19 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-18 16:11 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-18 11:19 UTCEG score recompute
- 2026-10-17 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-17 14:49 UTCEG score recompute
- 2026-10-17 14:49 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-16 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-16 13:28 UTCEG score recompute
- 2026-10-16 13:27 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-15 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-15 12:07 UTCEG score recompute
- 2026-10-15 12:07 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-14 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-14 10:45 UTCEG score recompute
- 2026-10-14 10:44 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-13 16:26 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-13 09:22 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-12 21:24 UTCEG score recompute
- 2026-10-12 16:27 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-12 08:02 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-12 03:43 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 23:22 UTCEG score recompute
- 2026-10-11 23:22 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 19:03 UTCEG score recompute
- 2026-10-11 19:03 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 14:45 UTCEG score recompute
- 2026-10-11 14:45 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 13:39 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-11 10:27 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 06:09 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-11 01:51 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-10 21:31 UTCEG score recompute
- 2026-10-10 21:31 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-10 19:54 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-10 17:10 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-10 12:52 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-10 08:34 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-10 04:16 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 23:58 UTCEG score recompute
- 2026-10-09 23:57 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 20:00 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-09 19:39 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 15:21 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 11:02 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 06:45 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-09 02:26 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 22:08 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 17:50 UTCEG score recompute
- 2026-10-08 17:50 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 16:34 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-08 13:27 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 09:07 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 04:49 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-08 00:31 UTCEG score recompute
- 2026-10-08 00:31 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-07 23:39 UTCEPSS rescoreEPSS 39% · 98th percentile
- 2026-10-07 20:13 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-07 15:55 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-07 11:34 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-07 07:13 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
- 2026-10-07 02:55 UTCGHSA enrichmentGHSA-f2wh-c6mm-3vrx · GitHub CVSS 7.8
Publicly available exploits
(5 references)Public exploit code is referenced for this CVE (1 Metasploit module, 3 Exploit-DB entries, 1 GitHub PoC). No release with the fix is confirmed, so defenders should restrict or isolate affected systems accordingly until one is applied.
- Exploit-DBEDB-26554✓ verifiedPublished Jul 2, 2013
Microsoft Windows - 'EPATHOBJ::pprFlattenRec' Local Privilege Escalation (Metasploit)
Open source ↗ - Metasploitexploit/windows/local/ppr_flatten_rec✓ verifiedPublished Jul 1, 2013
Windows EPATHOBJ::pprFlattenRec Local Privilege Escalation
Open source ↗ - Exploit-DBEDB-25912✓ verifiedPublished Jun 3, 2013
Microsoft Windows NT/2000/2003/2008/XP/Vista/7/8 - 'EPATHOBJ' Local Ring
Open source ↗ - Exploit-DBEDB-25611✓ verifiedPublished May 21, 2013
Microsoft Windows - Win32k!EPATHOBJ::pprFlattenRec Uninitialized Next Pointer Testcase
Open source ↗ - GitHub PoCExploitCN/CVE-2013-3660-x64-WIN7Published Jan 29, 2022
CVE-2013-3660的x64 win7平台EXP源代码,成功率100%。
Open source ↗
Related CVEs(same CWE)
Same CWE
10 shownCWE-119
- CVE-2013-3557EG 5.0MEDIUM
- CVE-2013-3341EG 10.0EPSS p93HIGH
- CVE-2013-3340EG 10.0EPSS p92HIGH
- CVE-2013-3339EG 10.0EPSS p93HIGH
- CVE-2013-3338EG 10.0EPSS p93HIGH
- CVE-2013-3337EG 10.0EPSS p93HIGH
- CVE-2013-3335EG 10.0EPSS p93HIGH
- CVE-2013-3334EG 10.0EPSS p93HIGH
- CVE-2013-3333EG 10.0EPSS p93HIGH
- CVE-2013-3332EG 10.0EPSS p93HIGH
Frequently asked(6)
What is CVE-2013-3660?
When was CVE-2013-3660 made public?
Is CVE-2013-3660 actively exploited?
What is the CVSS score of CVE-2013-3660?
Which products are affected by CVE-2013-3660?
How do I remediate CVE-2013-3660?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2013-3660
Is Your Infrastructure Affected by CVE-2013-3660?
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