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CVE-2026-73324 (GCVE-0-2026-73324)

Vulnerability from cvelistv5 – Published: 2026-09-09 13:31 – Updated: 2026-09-09 13:31
VLAI
Title
VLC media player 3.0.0 through 3.0.23 Heap Out-of-Bounds Read via Unterminated RealRTSP Response Line
Summary
VLC media player copies an RTSP response line into a fixed buffer without guaranteeing termination and then treats that buffer as a C string. RtspReadLine in modules/access/rtsp/access.c calls strncpy with the full buffer length, which writes no terminator when the source line is at least as long as the destination, and rtsp_get in modules/access/rtsp/rtsp.c allocates that buffer as BUF_SIZE bytes and passes it to strdup. When a server returns a line of 4096 bytes or more, strdup measures its length past the end of the allocation and copies adjacent heap bytes until an incidental zero byte. Because the affected line is the Session header, the disclosed bytes are retained as the session identifier and sent back to the server on every subsequent request, so the operator of a hostile server reads heap memory from the client rather than inferring it. The attacker controls the line length and therefore how far the read runs. A single playlist entry naming a realrtsp URL is sufficient. The module is a build-time option, disabled in some distribution packages and enabled in the official VideoLAN builds.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
VideoLAN VLC media player Affected: 3.0.0 , ≤ 3.0.23 (semver)
    cpe:2.3:a:videolan:vlc_media_player:*:*:*:*:*:*:*:*
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Date Public
2026-08-23 00:00
Credits
Fabian Wahle (Hap Security)
Show details on NVD website
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          "url": "https://github.com/videolan/vlc"
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    "assignerShortName": "VulnCheck",
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    "datePublished": "2026-09-09T13:31:59.019Z",
    "dateReserved": "2026-08-11T21:47:14.059Z",
    "dateUpdated": "2026-09-09T13:31:59.019Z",
    "state": "PUBLISHED"
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    "redhat_vex": {
      "current_release_date": "2026-09-09T16:11:11+00:00",
      "cve": "CVE-2026-73324",
      "id": "CVE-2026-73324",
      "initial_release_date": "2026-09-09T13:31:59.019000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "vlc: VLC media player: Information disclosure via unterminated RTSP response line",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73324.json",
      "version": "3"
    }
  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.