CyberSecBulletin
CVE-2023-2977NVD status: Modified

OpenSC: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2023-2977 is a high-severity out-of-bounds read vulnerability in OpenSC, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected OpenSC versions: opensc-0.23.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of OpenSC you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
OpenSCOpenSCopensc-0.23.0Not stated
Red HatEnterprise Linux8.0; 9.0Not stated

Version data comes from the organisation that assigned the CVE. 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
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.1HighNVD
CVSS 3.17.1HighCISA (ADP)

Official description

A vulnerbility was found in OpenSC. This security flaw cause a buffer overrun vulnerability in pkcs15 cardos_have_verifyrc_package. The attacker can supply a smart card package with malformed ASN1 context. The cardos_have_verifyrc_package function scans the ASN1 buffer for 2 tags, where remaining length is wrongly caculated due to moved starting pointer. This leads to possible heap-based buffer oob read. In cases where ASAN is enabled while compiling this causes a crash. Further info leak or more damage is possible.

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

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in OpenSC

All OpenSC vulnerabilities

Recent Out-of-bounds Read vulnerabilities

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