CyberSecBulletin
CVE-2017-8291Exploited in the wildNVD status: Analyzed

Artifex Ghostscript Type Confusion

Published Updated By the CyberSecBulletin desk

CVE-2017-8291 is a high-severity access of resource using incompatible type vulnerability in Ghostscript from Artifex, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 9.21 as the first without the flaw, so updating Ghostscript to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on May 24, 2022, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Ghostscript to 9.21 or a later version.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
ArtifexGhostscriptbefore 9.219.21
DebianDebian Linux8.0Not stated
Red HatEnterprise Linux Desktop6.0; 7.0Not stated
Red HatEnterprise Linux EUS7.3; 7.4; 7.5; 7.6; 7.7Not stated
Red HatEnterprise Linux Server6.0; 7.0Not stated
Red HatEnterprise Linux Server AUS7.3; 7.4; 7.6; 7.7Not stated
Red HatEnterprise Linux Server TUS7.3; 7.6; 7.7Not stated
Red HatEnterprise Linux Workstation6.0; 7.0Not stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)
CVSS 2.06.8MediumNVD

Official description

Artifex Ghostscript through 2017-04-26 allows -dSAFER bypass and remote command execution via .rsdparams type confusion with a "/OutputFile (%pipe%" substring in a crafted .eps document that is an input to the gs program, as exploited in the wild in April 2017.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Access of Resource Using Incompatible Type

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

More Access of Resource Using Incompatible Type vulnerabilities (CWE-843)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other vulnerabilities in Ghostscript

All Ghostscript vulnerabilities

Recent Access of Resource Using Incompatible Type vulnerabilities

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