Microsoft Excel Featheader Record Memory Corruption Vulnerability

CheckOps priority index

7.4/10 Patch within 7 days

Severity7.8

Probability8.4

Exploitation3/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 84.0% higher than 99.7% of CVEs

CVSS 3.1 7.8 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:

Exploited for 1,707 days 03 Mar 2022

CISA due date 24 Mar 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)03 Mar 2022
Exploited in EUVD (ENISA)03 Mar 2022
Used by ransomwareno
EPSS above 10 %84.0%
No account, over the networkno

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer 2003 SP3; Office Excel Viewer SP1 and SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allows remote attackers to execute arbitrary code via a spreadsheet with a FEATHEADER record containing an invalid cbHdrData size element that affects a pointer offset, aka "Excel Featheader Record Memory Corruption Vulnerability."

Affected products

Excel

Weaknesses (CWE)

CWE-94

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

11 Nov 2009
Published
03 Mar 2022
Exploitation reported (ENISA)
03 Mar 2022
Added to the KEV catalog
24 Mar 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 84.0%

References

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