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CVE-2024-23674NVD status: Deferred

online-ausweis-funktion: Authentication Bypass by Spoofing

CVE-2024-23674 is a critical-severity authentication bypass by spoofing vulnerability in online-ausweis-funktion from Ausweisapp, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected online-ausweis-funktion versions: 2024-02-15 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.73% chance of exploitation within 30 days, higher than 55% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of online-ausweis-funktion you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  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
Ausweisapponline-ausweis-funktion2024-02-15 and earlierNot 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
NetworkCan be exploited remotely over a network, including the internet.
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
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

The Online-Ausweis-Funktion eID scheme in the German National Identity card through 2024-02-15 allows authentication bypass by spoofing. A man-in-the-middle attacker can assume a victim's identify for access to government, medical, and financial resources, and can also extract personal data from the card, aka the "sPACE (Spoofing Password Authenticated Connection Establishment)" issue. This occurs because of a combination of factors, such as insecure PIN entry (for basic readers) and eid:// deeplinking. The victim must be using a modified eID kernel, which may occur if the victim is tricked into installing a fake version of an official app. NOTE: the BSI position is "ensuring a secure operational environment at the client side is an obligation of the ID card owner."

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

The underlying weakness: Authentication Bypass by Spoofing

This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.

More Authentication Bypass by Spoofing vulnerabilities (CWE-290)

Timeline

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

References

Recent Authentication Bypass by Spoofing vulnerabilities

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