Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcd4b61d65c98173…

MALICIOUS

PDF

72.8 KB Created: 2020-11-27 14:23:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 94034a0655a48da675951d6f0d6bfcd1 SHA-1: 1ff4b229a717941004fdcf0219f5d45f1980ca24 SHA-256: dcd4b61d65c98173935b056e908cbabfaf88b344e230531d4bf1557dc7c46991
254 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to redirector infrastructure, specifically identified by the 'PDF_MALICIOUS_REDIRECTOR_LINK' and 'PDF_SEO_LINK_FARM' heuristics. The primary malicious URL identified is 'https://gettraff.ru/123?utm_term=cuento+para+pensar+ni%25C3%25B1os', which is used in an SEO-based phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gettraff.ru/123?utm_term=cuento+para+pensar+ni%25C3%25B1os In PDF document text
    • https://cdn-cms.f-static.net/uploads/4394068/normal_5f9d6d536c85b.pdfIn PDF document text
    • https://sotufipepu.weebly.com/uploads/1/3/4/5/134595957/8080681.pdfIn PDF document text
    • https://dezusopivelisuk.weebly.com/uploads/1/3/4/7/134734284/cd09203a406.pdfIn PDF document text
    • https://dunojezeb.weebly.com/uploads/1/3/4/5/134586234/d09b3e67be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373757/normal_5fbfe83fe9da1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b3cd0f3-f459-4e86-98f0-b5fb3ec442cc/mastering_physics_textbook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb808af1-b940-4e16-945e-9c7fbeb3f0f6/52947311476.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce83c698-f2b4-43d6-8895-38a651bc10bc/gotowufexeguwoza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f9943bf-51a5-4157-b919-4de780588f28/1357194927.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/714271d7-c991-4560-90a1-7f3d637edb46/unblocked_gun_games_76.pdfIn PDF document text
    • https://s3.amazonaws.com/fenatagazise/kismat_bobby_deol_movie_song.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0af3da61-7a25-4df1-9698-460da438cb26/kisoburixunaturuxome.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/183adf49-8507-427b-98a0-e431e9ed8f12/29729370089.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c87b7c8b-e27a-4246-b929-bba6f2bb56f5/will_the_circle_be_unbroken_bioshock_chords.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e91f353-8741-4edd-ada5-c20ec8a5a08b/1938285615.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87fa2922-705a-4533-b373-810f53f798cd/84400547929.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE28 4900 bytes
SHA-256: 7794e0302502a4bee6ca7d0f69024087b03a099cd7854bafdb9ff96cf45253be
font_01_sfnt_off0000ee91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE91 11604 bytes
SHA-256: b240f056703e2446c90371cff82f2797d860163247053653777c3b0e8409c73f