CVE-2019-20788: canonical ubuntu_linux Integer Overflow or Wraparound
CVSS: 9.8v3.1CriticalModified
AliasesMGASA-2020-0207UBUNTU-CVE-2019-20788DEBIAN-CVE-2019-20788
Published 23-04-2020Last modified 05-08-2024
Vulnerability summary
CVE-2019-20788 is a critical (CVSS 9.8) Integer Overflow or Wraparound vulnerability in canonical ubuntu_linux. EPSS estimates a 2.50% chance of exploitation in the next 30 days, higher than 84.4% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
9.8/10
010
Critical · v3.1 (NVD)EPSS score
2.50%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github
Advisory lineage
Upstream 0 · Downstream 10 · Related 6Timeline
- 23-04-2020PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large height or width value. NOTE: this may overlap CVE-2019-15690.
CVSS metrics
4 scores · 3 sources · 2 versionsCritical 9.8Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
High 7.5Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:P/I:P/A:PSourcesSingle source
EPSS trend
Probability
2.50%
Chance of exploitation in the next 30 days
Percentile
84%
Versus all other CVEs
30-day change
0.00 pp
From 2.50% on 19-09-2026
19-09-202619-10-2026
EPSS score2.50%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundGhsl 2020 064 Libvnc Libvncclient
Maturity: poc
Weaknesses
CWE · root cause- CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
Siemens6 products
- simatic_itc1500_firmware≥ 3.0.0.0, < 3.2.1.0
- simatic_itc1500_pro_firmware≥ 3.0.0.0, < 3.2.1.0
- simatic_itc1900_firmware≥ 3.0.0.0, < 3.2.1.0
- simatic_itc1900_pro_firmware≥ 3.0.0.0, < 3.2.1.0
- simatic_itc2200_firmware≥ 3.0.0.0, < 3.2.1.0
Debian2 products
- libvncserver< 0.9.12+dfsg-9
- debian_linuxEOL8.0 | 9.0
Ubuntu2 products
- libvncserver< 0.9.10+dfsg-3ubuntu0.16.04.4 | < 0.9.11+dfsg-1ubuntu1.2
- x11vncAll versions (No fix recorded)
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 18.04 | 18.10
Libvnc_project1 product
- libvncserver≤ 0.9.12
Mageia1 product
- libvncserver< 0.9.12-2.3.mga7
6 vendors · 13 products
References
11 links- github.com/LibVNC/libvncserver/commit/54220248886b5001fbbb9fa73c4e1a2cb9413fedX Refsource MISCPatchThird Party Advisory
- lists.opensuse.org/opensuse-security-announce/2020-05/msg00027.htmlVendor AdvisoryX Refsource SUSEMailing ListThird Party Advisory
- securitylab.github.com/advisories/GHSL-2020-064-libvnc-libvncclientX Refsource MISCExploitThird Party Advisory
