Cyber Resilience

CVE-2023-26258

CriticalPublic PoC

Published: 03 July 2023

Published
03 July 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.8077 99.2th percentile
Risk Priority 68 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-26258 is a critical-severity Incorrect Authorization (CWE-863) vulnerability in Arcserve Udp. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

Arcserve UDP through version 9.0.6034 contains an authentication bypass vulnerability in its web service implementation. The getVersionInfo method exposed at WebServiceImpl/services/FlashServiceImpl returns an AuthUUID token that can be replayed against VirtualStandbyServiceImpl to establish a fully authenticated administrator session without supplying credentials. The flaw is tracked as CWE-863 and carries a CVSS 3.1 score of 9.8.

An unauthenticated remote attacker can invoke the leaking endpoint, capture the token, and obtain a persistent administrative session. With that session the attacker can invoke any management operation, including backup job manipulation, data exfiltration, or arbitrary command execution on protected systems.

Arcserve advisory KB000015720 addresses the issue and directs customers to upgrade to a fixed build. The associated MDSEC disclosure demonstrates remote code execution by chaining the obtained session to administrative tasks. The vulnerability’s EPSS score has remained above 0.80 since disclosure, indicating sustained exploitation interest.

EU & UK References

Vulnerability details

Arcserve UDP through 9.0.6034 allows authentication bypass. The method getVersionInfo at WebServiceImpl/services/FlashServiceImpl leaks the AuthUUID token. This token can be used at /WebServiceImpl/services/VirtualStandbyServiceImpl to obtain a valid session. This session can be used to execute any task as administrator.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

arcserve
udp
≤ 9.0.6034

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-863

Periodic review and update of procedures reduces incorrect authorization implementations over time.

addresses: CWE-863

Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.

addresses: CWE-863

Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.

addresses: CWE-863

The authorization process and usage restrictions help prevent incorrect authorization for remote access types.

addresses: CWE-863

Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.

addresses: CWE-863

Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.

addresses: CWE-863

Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.

addresses: CWE-863

Ensures authorization decisions for external system use are correctly implemented and enforced.

References