cbcvebase.
CVE-2023-31137
published 2023-05-09

CVE-2023-31137: MaraDNS is open-source software that implements the Domain Name System (DNS). In version 3.5.0024 and prior, a remotely exploitable integer underflow…

PriorityP339high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.14%
63.1th percentile
MaraDNS is open-source software that implements the Domain Name System (DNS). In version 3.5.0024 and prior, a remotely exploitable integer underflow vulnerability in the DNS packet decompression function allows an attacker to cause a Denial of Service by triggering an abnormal program termination. The vulnerability exists in the `decomp_get_rddata` function within the `Decompress.c` file. When handling a DNS packet with an Answer RR of qtype 16 (TXT record) and any qclass, if the `rdlength` is smaller than `rdata`, the result of the line `Decompress.c:886` is a negative number `len = rdlength - total;`. This value is then passed to the `decomp_append_bytes` function without proper validation, causing the program to attempt to allocate a massive chunk of memory that is impossible to allocate. Consequently, the program exits with an error code of 64, causing a Denial of Service. One proposed fix for this vulnerability is to patch `Decompress.c:887` by breaking `if(len <= 0)`, which has been incorporated in version 3.5.0036 via commit bab062bde40b2ae8a91eecd522e84d8b993bab58.

Affected

13 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debianmaradns< maradns 2.0.13-1.4+deb11u1 (bullseye)maradns 2.0.13-1.4+deb11u1 (bullseye)
fedoraprojectfedora
fedoraprojectfedora
maradnsmaradns< 3.4.103.4.10
maradnsmaradns>= 0 < 2.0.13-1.4+deb11u12.0.13-1.4+deb11u1
maradnsmaradns>= 0 < 2.0.13-1.4+deb11u1build0.20.04.12.0.13-1.4+deb11u1build0.20.04.1
maradnsmaradns>= 0 < 2.0.13-1.4+deb11u1build0.22.04.12.0.13-1.4+deb11u1build0.22.04.1
maradnsmaradns>= 0 < 2.0.13-1ubuntu0.1~esm12.0.13-1ubuntu0.1~esm1
maradnsmaradns>= 0 < 2.0.13-1.2ubuntu0.1~esm12.0.13-1.2ubuntu0.1~esm1
maradnsmaradns>= 3.5.0001 < 3.5.00363.5.0036
samboymaradns<= 3.5.0024

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_ubuntu7.5HIGH
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