CVE-2024-0553Public exploitNetwork attack vector

Sensitive-data inference via RSA-PSK timing differences

Published Jan 16, 2024 · Updated Mar 24, 2026

Timing side channel in GnuTLS 3.8.0 through 3.8.2 allows remote attackers to infer sensitive data via RSA-PSK handshakes. The _gnutls_proc_rsa_psk_client_kx routine in lib/auth/rsa_psk.c produces measurably different response times for malformed RSA ciphertexts and correctly padded PKCS#1 v1.5 inputs. Exploitation requires an RSA-PSK server and enough chosen-ciphertext observations to resolve nanosecond-scale differences; no integrity or availability impact is reported.

CVSS severity5.9
Medium
EPSS probability1.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Timing side channel in GnuTLS 3.8.0 through 3.8.2 allows remote attackers to infer sensitive data via RSA-PSK handshakes. The _gnutls_proc_rsa_psk_client_kx routine in lib/auth/rsa_psk.c produces measurably different response times for malformed RSA ciphertexts and correctly padded PKCS#1 v1.5 inputs. Exploitation requires an RSA-PSK server and enough chosen-ciphertext observations to resolve nanosecond-scale differences; no integrity or availability impact is reported.

The record

CVE
CVE-2024-0553
Published
Jan 16, 2024
Updated
Mar 24, 2026
Vendor
Red Hat
Product
Red Hat Enterprise Linux 8
Classifications
CWE-203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 16, 2024CVE publishedPublication date reported by the CVE source.
  2. Mar 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Red Hat · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 9.2 Extended Update SupportAffected versions are unavailable in this record.
Red Hat · Red Hat Logging 5.8 for RHEL 9Affected versions are unavailable in this record.
Red Hat · Red Hat OpenShift Data Foundation 4.15 for RHEL 9Affected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
GnuTLS Project · GnuTLSversion=3.8.0 <3.8.3
Red Hat · Red Hat Enterprise Linux 8.8 Extended Update SupportAffected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 8.6 Extended Update SupportAffected versions are unavailable in this record.

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.9Amazon LinuxCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-203Observable Discrepancy

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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