Timing Side-Channel in Scalar Multiplication for Non-NIST EC Curves
Noroxi assessment
Priority: Monitor (action score 14/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.26% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
- Fixed version: OpenSSL OpenSSL 3.0.23, 3.4.8, 3.5.9; azl3 cloud-hypervisor 52.0.152-1 on Azure Linux 3.0 Release Notes; azl3 edk2 20240524git3e722403cd16-20 on Azure Linux 3.0 20240524git3e722403cd16-21.
Low priority for now. Upgrade to OpenSSL OpenSSL 3.0.23, 3.4.8, 3.5.9; azl3 cloud-hypervisor 52.0.152-1 on Azure Linux 3.0 Release Notes; azl3 edk2 20240524git3e722403cd16-20 on Azure Linux 3.0 20240524git3e722403cd16-21 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Issue summary: The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature operations with curves that do not have a dedicated implementation leaks information about the secret nonce through timing. Impact summary: An attacker able to measure signing times may learn information about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy Description: The generic elliptic-curve scalar multiplication used for curves that do not have a dedicated constant-time implementation pads the secret scalar with non-constant-time BIGNUM operations, so the time taken depends on the value of the secret scalar derived from the ECDSA and SM2 nonce. The leak is very small; observing it requires a large number of measurements. The effect is largest for curves whose group order lies on a machine-word boundary, such as brainpoolP384r1. Applications using ECDSA signing over the Brainpool and other generic prime curves, and SM2 signing on platforms that use the generic implementation, are vulnerable to this issue. The NIST curves P-256, P-384 and P-521 use dedicated constant-time implementations and are not affected. FIPS Impact: no The FIPS modules are not affected: the approved NIST curves used in the FIPS provider have dedicated constant-time implementations and do not use the affected code path.
- Published
- Sep 29, 2026
- Updated
- Oct 8, 2026
- EPSS
- 0.3% · 17th percentile
- CWE
- CWE-208
Report tools
Action score
14
Monitor
Low priority for now.
- CVSS
- 14 / 40 · 3.7 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| openssl | openssl | cpe:2.3:a:openssl:openssl |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- openssl openssl1.0.2 and later · before 1.0.2zs
- openssl openssl1.1.1 and later · before 1.1.1zj
- openssl openssl3.0.0 and later · before 3.0.23
- openssl openssl3.4.0 and later · before 3.4.8
- openssl openssl3.5.0 and later · before 3.5.9
- openssl openssl3.6.0 and later · before 3.6.5
- openssl openssl4.0.0 and later · before 4.0.3
Versions reported by the vendor
Affected version ranges reported by the assigning authority (openssl). Independent of NVD's CPE analysis and usually ahead of it.
OpenSSL OpenSSL
- 4.0.0 and later · before 4.0.3affected · semver
- 3.6.0 and later · before 3.6.5affected · semver
- 3.5.0 and later · before 3.5.9affected · semver
- 3.4.0 and later · before 3.4.8affected · semver
- 3.0.0 and later · before 3.0.23affected · semver
- 1.1.1 and later · before 1.1.1zjaffected
- 1.0.2 and later · before 1.0.2zsaffected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.21 | openssl | from 1.0.2 · before 3.3.7-r2 | 3.3.7-r2 |
| Debian:12 | openssl | all versions | — |
| Debian:13 | openssl | before 3.5.7-1~deb13u3 | 3.5.7-1~deb13u3 |
| Debian:14 | openssl | before 3.6.5-1 | 3.6.5-1 |
| Red Hat:hummingbird:1 | openssl | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-config-fips | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-devel | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-devel-engine | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-fips-provider-upstream | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-libs | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl-perl | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl3 | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl3-devel | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl3-devel-engine | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| Red Hat:hummingbird:1 | openssl3-libs | before 0:3.5.9-0.1.hum1 | 0:3.5.9-0.1.hum1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | openssl-3 | before 3.0.8-150500.5.80.1 | 3.0.8-150500.5.80.1 |
| SUSE:Linux Enterprise Micro 5.3 | openssl-3 | before 3.0.8-150400.4.101.1 | 3.0.8-150400.4.101.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP7 | openssl-3 | before 3.5.0-150700.5.53.2 | 3.5.0-150700.5.53.2 |
| SUSE:Linux Enterprise Server 15 SP6-LTSS | openssl-3 | before 3.1.4-150600.5.67.1 | 3.1.4-150600.5.67.1 |
Same product
openssl: all recordsOther highest-scoring records for the same primary product.
- CVE-2014-0160The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly handle Heartbeat Extension packets, which allows remKEV90Now
- CVE-2021-3711SM2 Decryption Buffer Overflow65This week
- CVE-2003-0545Double free vulnerability in OpenSSL 0.9.7 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code 65This week
- CVE-2016-2108The ASN.1 implementation in OpenSSL before 1.0.1o and 1.0.2 before 1.0.2c allows remote attackers to execute arbitrary code or cause a denia62This week
- CVE-2016-6309statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote attackers to cause a den60This week
- CVE-2022-3786X.509 Email Address Variable Length Buffer Overflow58Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| OpenSSL OpenSSL | 3.0.23 | Vendor (CNA) |
| OpenSSL OpenSSL | 3.4.8 | Vendor (CNA) |
| OpenSSL OpenSSL | 3.5.9 | Vendor (CNA) |
| OpenSSL OpenSSL | 3.6.5 | Vendor (CNA) |
| OpenSSL OpenSSL | 4.0.3 | Vendor (CNA) |
| azl3 cloud-hypervisor 52.0.152-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 edk2 20240524git3e722403cd16-20 on Azure Linux 3.0 | 20240524git3e722403cd16-21 · Release Notes | Microsoft (MSRC) |
| azl3 kata-containers 4.1.0.kata0-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 openssl 3.3.7-6 on Azure Linux 3.0 | 3.3.7-7 · Release Notes | Microsoft (MSRC) |
| azl3 openvmm 0.1.0-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 qemu 10.1.0-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 rust 1.75.0-31 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 rust 1.96.1-2 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| alpine:openssl | 3.3.7-r2 · Alpine:v3.21 | Package registry (OSV) |
| debian:openssl | 3.5.7-1~deb13u3 · Debian:13 | Package registry (OSV) |
| red hat:openssl | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-config-fips | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-devel | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-devel-engine | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-fips-provider-upstream | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-libs | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl-perl | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl3 | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl3-devel | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl3-devel-engine | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:openssl3-libs | 0:3.5.9-0.1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| suse:openssl-3 | 3.0.8-150500.5.80.1 · SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayOct 15, 2026+15 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Igor Ustinovremediation developer
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-548750 days apartNon-Constant-Time SM2 Scalar Multiplication on ARM64 and RISC-V14Monitor
- CVE-2026-776960 days apartTiming Side-Channel in SM2 Signature Generation14Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- low · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-208 · Observable Timing DiscrepancyCVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Exploit maturity— → none
- Fix✗ → ✓
- CVSS— → 3.7
- Severity— → low
- SSVC exploitation— → none
For records you follow, these changes also arrive as notifications. →
References
Show all references (4 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.