CVE-2020-27737 Memory corruption in APOGEE PXC Compact (BACnet)
Attackers can cause denial of service or leak memory via malformed DNS responses in Siemens building automation and Nucleus NET products.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2020-27737?
CVE-2020-27737 is a medium-severity memory corruption vulnerability in Siemens APOGEE PXC Compact (BACnet), published on 22 Apr 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions < V3.5.5), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.20), APOGEE PXC Modular (BACnet) (All versions < V3.5.5), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.20), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS response parsing functionality does not properly validate various length and counts of the records. The parsing of malformed responses could result in a read past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition or leak the memory past the allocated structure.
Weakness: CWE-125
Which versions are affected by CVE-2020-27737?
It affects 5 products.
Products include Siemens Nucleus Net, Siemens Nucleus Readystart V3, Siemens Nucleus Readystart V4, Siemens Nucleus Source Code, Siemens Simotics Connect 400 Firmware.
How do I fix CVE-2020-27737?
No fix has been published for CVE-2020-27737 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2020-27737 being exploited?
There is no known exploitation of CVE-2020-27737 in the wild and no public exploit code.
Other vulnerabilities in Siemens APOGEE PXC Compact (BACnet)
- CVE-2020-15795 Memory corruption in APOGEE PXC Compact (BACnet)
- CVE-2020-27009 Memory corruption in APOGEE PXC Compact (BACnet)
- CVE-2020-27736 Memory corruption in APOGEE PXC Compact (BACnet)
- CVE-2020-27738 Memory corruption in APOGEE PXC Compact (BACnet)
- CVE-2021-25677 Other in APOGEE PXC Compact (BACnet)
Sources
Also known as GHSA-j94w-w786-mv9m.