CVE-2019-20840

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Source
https://nvd.nist.gov/vuln/detail/CVE-2019-20840
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2019-20840.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2019-20840
Downstream
Related
Published
2020-06-17T16:15:11Z
Modified
2025-10-15T10:49:33.159571Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.

References

Affected packages

Git / github.com/libvnc/libvncserver

Affected ranges

Type
GIT
Repo
https://github.com/libvnc/libvncserver
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
0cf1400c61850065de590d403f6d49e32882fd76

Affected versions

LibVNCServer-0.*

LibVNCServer-0.9.10
LibVNCServer-0.9.11
LibVNCServer-0.9.12
LibVNCServer-0.9.8
LibVNCServer-0.9.9

Other

X11VNC_0_9_10
X11VNC_0_9_11
X11VNC_0_9_12
X11VNC_0_9_7
X11VNC_0_9_8
X11VNC_0_9_9
X11VNC_REL_0_9_4
X11VNC_REL_0_9_5
X11VNC_REL_0_9_6

Database specific

vanir_signatures

[
    {
        "target": {
            "function": "hybiReadAndDecode",
            "file": "libvncserver/ws_decode.c"
        },
        "id": "CVE-2019-20840-10709c66",
        "signature_type": "Function",
        "signature_version": "v1",
        "deprecated": false,
        "source": "https://github.com/libvnc/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76",
        "digest": {
            "function_hash": "180079713415210745791807162750284308920",
            "length": 4063.0
        }
    },
    {
        "target": {
            "file": "libvncserver/ws_decode.c"
        },
        "id": "CVE-2019-20840-337dc46d",
        "signature_type": "Line",
        "signature_version": "v1",
        "deprecated": false,
        "source": "https://github.com/libvnc/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76",
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "280535027786460026972189112772063445853",
                "50701751959996758734036103654922009095",
                "152558449667183412663568482169208692828",
                "327930894662464802945272025504953063997",
                "187881109947118880620593900587007315645",
                "215302365506936472057092840460876039458",
                "50659555013314031717534322792322098385",
                "184898503279201702730802996537756075167",
                "96434419174010811701165366566747251317",
                "176232627971923197157543118542926500038"
            ]
        }
    }
]