CVE-2020-35857
Stack consumption in trust-dns-server
An issue was discovered in the trust-dns-server crate before 0.18.1 for Rust. DNS MX and SRV null targets are mishandled, causing stack consumption.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
7.5
An issue was discovered in the trust-dns-server crate before 0.18.1 for Rust. DNS MX and SRV null targets are mishandled, causing stack consumption.
- Record
CVE-2020-35857- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-400
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in the trust-dns-server crate before 0.18.1 for Rust. DNS MX and SRV null targets are mishandled, causing stack consumption.
- Record
CVE-2020-35857- Updated
- 2026-11-02
EUVDEUVD-2021-1559 No score
An issue was discovered in the trust-dns-server crate before 0.18.1 for Rust. DNS MX and SRV null targets are mishandled, causing stack consumption.
- Record
EUVD-2021-1559- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4cww-f7w5-x525
7.5
Stack consumption in trust-dns-server
There's a stack overflow leading to a crash and potential DOS when processing additional records for return of MX or SRV record types from the server. This is only possible when a zone is configured with a null target for MX or SRV records. Prior to 0.16.0 the additional record processing was not supported by trust-dns-server. There Are no known issues with upgrading from 0.16 or 0.17 to 0.18.1. The remidy should be to upgrade to 0.18.1. If unable to do so, MX, SRV or other record types with a target to the null type, should be avoided.
- Record
GHSA-4cww-f7w5-x525- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVGHSA-4cww-f7w5-x525
7.5
Stack consumption in trust-dns-server
There's a stack overflow leading to a crash and potential DOS when processing additional records for return of MX or SRV record types from the server. This is only possible when a zone is configured with a null target for MX or SRV records. Prior to 0.16.0 the additional record processing was not supported by trust-dns-server. There Are no known issues with upgrading from 0.16 or 0.17 to 0.18.1. The remidy should be to upgrade to 0.18.1. If unable to do so, MX, SRV or other record types with a target to the null type, should be avoided.
- Record
GHSA-4cww-f7w5-x525- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVRUSTSEC-2020-0001
7.5
Stack overflow when resolving additional records from MX or SRV null targets
There's a stack overflow leading to a crash and potential DOS when processing additional records for return of MX or SRV record types from the server.
This is only possible when a zone is configured with a null target for MX or SRV records, i.e. '.'.
Example effected zone record:
no-service 86400 IN MX 0 .
Prior to 0.16.0 the additional record processing was not supported by trust-dns-server. There Are no known issues with upgrading from 0.16 or 0.17 to 0.18.1. The remidy should be to upgrade to 0.18.1. If unable to do so, MX, SRV or other record types with a target to the null type, should be avoided.
- Record
RUSTSEC-2020-0001- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
trust-dns-servercrates.io |
0.16.0 up to 0.18.1 | 0.18.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-35857 is a high vulnerability (CVSS 7.5) in Trust-dns-server Project Trust-dns-server, published January 6, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.46%, the 73rd percentile. Fixed in trust-dns-server 0.18.1.
References
rustsec.org/advisories/RUSTSEC-2020-0001.html
github.com/bluejekyll/trust-dns/commit/8b9eab05795fdc098976262853b2498055c7a8f3
nvd.nist.gov/vuln/detail/CVE-2020-35857
github.com/bluejekyll/trust-dns/issues/980
github.com/bluejekyll/trust-dns/pull/982
github.com/advisories/GHSA-4cww-f7w5-x525
github.com/bluejekyll/trust-dns
crates.io/crates/trust-dns-server