Malicious PDF — malware analysis report

Static analysis result for SHA-256 e6135e939e0d63ea…

MALICIOUS

PDF

40.0 KB Created: 2020-11-03 09:05:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27de23c08f89127741422150221ef993 SHA-1: 53424a1215d0c2a329bfdbd1174831186dd4ac9b SHA-256: e6135e939e0d63ea9fe45d8c6a4675365b95dedb8c56f3ca2bfd9d2487120d4a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector infrastructure. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains a URL that is also present in the embedded link list, suggesting an attempt to lure the user to a malicious site. The presence of a link farm heuristic further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.club/123?keyword=sheltered+english+instruction+pros+and+cons
    • https://natizupasa.weebly.com/uploads/1/3/1/4/131437725/fubazewi.pdf
    • https://cdn-cms.f-static.net/uploads/4385880/normal_5fa0fba40818b.pdf
    • https://kabolonopatine.weebly.com/uploads/1/3/4/2/134265344/todigudelona.pdf
    • https://cdn-cms.f-static.net/uploads/4373516/normal_5f8ab7a01133c.pdf
    • https://cdn-cms.f-static.net/uploads/4375515/normal_5f9cd59c018de.pdf
    • https://mefemanodi.weebly.com/uploads/1/3/1/4/131454269/0836f2c35d91f.pdf
    • https://cdn-cms.f-static.net/uploads/4376619/normal_5f9ae3d03882a.pdf
    • https://cdn-cms.f-static.net/uploads/4369777/normal_5f886c605d41d.pdf
    • https://wodedofa.weebly.com/uploads/1/3/4/3/134320626/b0933e22.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/sodoxi/bloons_tower_defense_4_expansion_unblocked.pdf
    • https://cdn.shopify.com/s/files/1/0431/8576/6564/files/harvard_summer_institute_on_college_admissions.pdf
    • https://s3.amazonaws.com/mejigavukolu/editing_to_word.pdf
    • https://s3.amazonaws.com/gupuso/lepebatadulobem.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005de6.bin
aff767af37d40065dc4e4b6d6c5f48602bc708e92e44096eed8a2e69f652bb19
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DE6 5436 bytes
font_01_sfnt_off0000705a.bin
cb5c3f9bde456d43470a096472643f5453a6b01fbcef206ae4082991bba93d8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x705A 10180 bytes