Malicious PDF — malware analysis report

Static analysis result for SHA-256 961f120a04155319…

MALICIOUS

PDF

47.5 KB Created: 2020-10-28 12:49:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 4254e9bd2c2b6666b8f300c04a1c4e30 SHA-1: 8f43187954abe9fa25554217177e56fc7acb4dc9 SHA-256: 961f120a0415531960b1baf8b9262b2fffa91e5fe10e0f0b8c328f486e2447c0
194 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external PDF files, suggesting a link farm or SEO manipulation tactic. One prominent link, disguised as a book title, redirects to known malicious infrastructure. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.link/123?keyword=the+case+for+christianity+answer+book+pdf In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366377/normal_5f9829d6870a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388611/normal_5f951721d8bf0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367289/normal_5f9045d4eaed7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414358/normal_5f97a0f979be1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383795/normal_5f936d5490c76.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382190/normal_5f95467e3c4fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385437/normal_5f9371d627656.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368251/normal_5f983e67a364f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379217/normal_5f8fc6b6585db.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366347/normal_5f9202212dca0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369493/normal_5f88a0ca5edcc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409000/normal_5f92edff15c38.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366317/normal_5f954d0dcaa3c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372073/normal_5f8e7a087b4ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425908/normal_5f9939badd63c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376852/normal_5f9202e68605e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376619/normal_5f9521c188ca4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/2f10a0dc-0c5d-4d0f-b36a-5d4f2cf68ed2/music_of_the_night.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/94f32dcc-0f1f-47dc-85af-eac7d8d96fa4/grammaire_progressive_du_francais_intermediaire_corriges.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6499148e-b068-4014-ba21-e3cd8035d7ad/32581452215.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/521c992b-5b75-4010-ac57-f41234c08d2e/wivenivedimesewipapefuke.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ad678f1-7dfc-4bd6-88bb-3aca529108b9/31823099534.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0484/7088/4514/files/lego_movie_2_video_game_apk.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006a71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6A71 5348 bytes
SHA-256: 9008674a541fd4058001fc3f1c1f4f15c7a2f86777a6b94616df15ffe8dd5eba
font_01_sfnt_off00007ca2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7CA2 11020 bytes
SHA-256: 04ce38d4dd5523147ac1628a8e15993fbef7b007c1cdab4138f6cde3670f4afb
font_02_sfnt_off0000a1cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA1CB 4324 bytes
SHA-256: ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230