CVE-2020-26263
- Source
- https://cve.org/CVERecord?id=CVE-2020-26263
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-26263.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2020-26263
- Aliases
- Downstream
- Published
- 2020-12-21T17:15:12.637Z
- Modified
- 2026-07-08T06:01:00.314551573Z
- Severity
-
- 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
- Summary
- [none]
- Details
-
tlslite-ng is an open source python library that implements SSL and TLS cryptographic protocols. In tlslite-ng before versions 0.7.6 and 0.8.0-alpha39, the code that performs decryption and padding check in RSA PKCS#1 v1.5 decryption is data dependant. In particular, the code has multiple ways in which it leaks information about the decrypted ciphertext. It aborts as soon as the plaintext doesn't start with 0x00, 0x02. All TLS servers that enable RSA key exchange as well as applications that use the RSA decryption API directly are vulnerable. This is patched in versions 0.7.6 and 0.8.0-alpha39. Note: the patches depend on Python processing the individual bytes in side-channel free manner, this is known to not the case (see reference). As such, users that require side-channel resistance are recommended to use different TLS implementations, as stated in the security policy of tlslite-ng.
- Database specific
{ "unresolved_ranges": [ { "source": "CPE_STRING", "cpes": [ "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha1:*:*:*:*:*:*" ], "vendor_product": "tlslite-ng_project:tlslite-ng", "extracted_events": [ { "introduced": "0.8.0-alpha1" }, { "last_affected": "0.8.0-alpha1" } ] } ] }- References
-
- https://github.com/tlsfuzzer/tlslite-ng/commit/c28d6d387bba59d8bd5cb3ba15edc42edf54b368
- https://github.com/tlsfuzzer/tlslite-ng/pull/438
- https://github.com/tlsfuzzer/tlslite-ng/pull/439
- https://github.com/tlsfuzzer/tlslite-ng/security/advisories/GHSA-wvcv-832q-fjg7
- https://pypi.org/project/tlslite-ng/
- https://securitypitfalls.wordpress.com/2018/08/03/constant-time-compare-in-python/
Affected packages
Git / github.com/tlsfuzzer/tlslite-ng
Affected ranges
- Type
- GIT
- Repo
- https://github.com/tlsfuzzer/tlslite-ng
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixedIntroducedLast affectedFixed
- Database specific
{ "cpe": [ "cpe:2.3:a:tlslite-ng_project:tlslite-ng:*:*:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha1:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha10:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha11:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha12:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha13:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha14:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha15:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha16:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha17:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha18:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha19:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha2:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha20:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha21:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha22:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha23:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha24:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha25:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha26:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha27:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha28:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha29:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha3:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha30:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha31:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha32:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha33:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha34:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha35:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha36:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha37:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha38:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha4:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha5:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha6:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha7:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha8:*:*:*:*:*:*", "cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha9:*:*:*:*:*:*" ], "source": [ "CPE_RANGE", "CPE_STRING", "REFERENCES" ], "extracted_events": [ { "introduced": "0" }, { "fixed": "0.7.6" }, { "introduced": "0.8.0-alpha1" }, { "last_affected": "0.8.0-alpha1" }, { "introduced": "0.8.0-alpha10" }, { "last_affected": "0.8.0-alpha10" }, { "introduced": "0.8.0-alpha11" }, { "last_affected": "0.8.0-alpha11" }, { "introduced": "0.8.0-alpha12" }, { "last_affected": "0.8.0-alpha12" }, { "introduced": "0.8.0-alpha13" }, { "last_affected": "0.8.0-alpha13" }, { "introduced": "0.8.0-alpha14" }, { "last_affected": "0.8.0-alpha14" }, { "introduced": "0.8.0-alpha15" }, { "last_affected": "0.8.0-alpha15" }, { "introduced": "0.8.0-alpha16" }, { "last_affected": "0.8.0-alpha16" }, { "introduced": "0.8.0-alpha17" }, { "last_affected": "0.8.0-alpha17" }, { "introduced": "0.8.0-alpha18" }, { "last_affected": "0.8.0-alpha18" }, { "introduced": "0.8.0-alpha19" }, { "last_affected": "0.8.0-alpha19" }, { "introduced": "0.8.0-alpha2" }, { "last_affected": "0.8.0-alpha2" }, { "introduced": "0.8.0-alpha20" }, { "last_affected": "0.8.0-alpha20" }, { "introduced": "0.8.0-alpha21" }, { "last_affected": "0.8.0-alpha21" }, { "introduced": "0.8.0-alpha22" }, { "last_affected": "0.8.0-alpha22" }, { "introduced": "0.8.0-alpha23" }, { "last_affected": "0.8.0-alpha23" }, { "introduced": "0.8.0-alpha24" }, { "last_affected": "0.8.0-alpha24" }, { "introduced": "0.8.0-alpha25" }, { "last_affected": "0.8.0-alpha25" }, { "introduced": "0.8.0-alpha26" }, { "last_affected": "0.8.0-alpha26" }, { "introduced": "0.8.0-alpha27" }, { "last_affected": "0.8.0-alpha27" }, { "introduced": "0.8.0-alpha28" }, { "last_affected": "0.8.0-alpha28" }, { "introduced": "0.8.0-alpha29" }, { "last_affected": "0.8.0-alpha29" }, { "introduced": "0.8.0-alpha3" }, { "last_affected": "0.8.0-alpha3" }, { "introduced": "0.8.0-alpha30" }, { "last_affected": "0.8.0-alpha30" }, { "introduced": "0.8.0-alpha31" }, { "last_affected": "0.8.0-alpha31" }, { "introduced": "0.8.0-alpha32" }, { "last_affected": "0.8.0-alpha32" }, { "introduced": "0.8.0-alpha33" }, { "last_affected": "0.8.0-alpha33" }, { "introduced": "0.8.0-alpha34" }, { "last_affected": "0.8.0-alpha34" }, { "introduced": "0.8.0-alpha35" }, { "last_affected": "0.8.0-alpha35" }, { "introduced": "0.8.0-alpha36" }, { "last_affected": "0.8.0-alpha36" }, { "introduced": "0.8.0-alpha37" }, { "last_affected": "0.8.0-alpha37" }, { "introduced": "0.8.0-alpha38" }, { "last_affected": "0.8.0-alpha38" }, { "introduced": "0.8.0-alpha4" }, { "last_affected": "0.8.0-alpha4" }, { "introduced": "0.8.0-alpha5" }, { "last_affected": "0.8.0-alpha5" }, { "introduced": "0.8.0-alpha6" }, { "last_affected": "0.8.0-alpha6" }, { "introduced": "0.8.0-alpha7" }, { "last_affected": "0.8.0-alpha7" }, { "introduced": "0.8.0-alpha8" }, { "last_affected": "0.8.0-alpha8" }, { "introduced": "0.8.0-alpha9" }, { "last_affected": "0.8.0-alpha9" } ] }
Affected versions
0.*
0.8.0-alpha1
0.8.0-alpha10
0.8.0-alpha11
0.8.0-alpha12
0.8.0-alpha13
0.8.0-alpha14
0.8.0-alpha15
0.8.0-alpha16
0.8.0-alpha17
0.8.0-alpha18
0.8.0-alpha19
0.8.0-alpha2
0.8.0-alpha20
0.8.0-alpha21
0.8.0-alpha22
0.8.0-alpha23
0.8.0-alpha24
0.8.0-alpha25
0.8.0-alpha26
0.8.0-alpha27
0.8.0-alpha28
0.8.0-alpha29
0.8.0-alpha3
0.8.0-alpha30
0.8.0-alpha31
0.8.0-alpha32
0.8.0-alpha33
0.8.0-alpha34
0.8.0-alpha35
0.8.0-alpha36
0.8.0-alpha37
0.8.0-alpha38
0.8.0-alpha4
0.8.0-alpha5
0.8.0-alpha6
0.8.0-alpha7
0.8.0-alpha8
0.8.0-alpha9
Other
fork-start
v0.*
v0.3.9x
v0.4.1
v0.4.2
v0.4.3
v0.4.8
v0.5.0
v0.5.0-beta3
v0.5.0-beta4
v0.5.0-beta6
v0.5.1
v0.6.0
v0.6.0-alpha1
v0.6.0-alpha2
v0.6.0-alpha3
v0.6.0-alpha4
v0.6.0-alpha5
v0.6.0-beta1
v0.7.0
v0.7.0-alpha1
v0.7.0-alpha2
v0.7.0-alpha3
v0.7.0-alpha4
v0.7.0-alpha5
v0.7.0-alpha6
v0.7.0-alpha7
v0.7.0-alpha8
v0.7.0-alpha9
v0.7.0-beta1
v0.7.1
v0.7.2
v0.7.3
v0.7.4
v0.7.5
v0.8.0-alpha1
v0.8.0-alpha2
v0.8.0-alpha3
v0.8.0-alpha4
v0.8.0-alpha5
v0.8.0-alpha6
v0.8.0-alpha7
v0.8.0-alpha8
v0.8.0-alpha9