Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a79036503ae7d6…

MALICIOUS

PDF

85.4 KB Created: 2021-03-24 07:09:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: b4ec40281a0dcc35b8b765aeb338f7d2 SHA-1: ca90433cd65faf0d9c801c30494f85051a200284 SHA-256: a5a79036503ae7d67a9c787a31a241d088e49c880298f0dd905440ff363f41bb
196 Risk Score

Malware Insights

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

The PDF contains a link farm and SEO redirector, masquerading as an "annual report" to entice users to download further content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://dugedepap.ru/123?utm_term=bharti+airtel+annual+report+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4501810/normal_5fc72601510d0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393502/normal_5fedbd4616e86.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445115/normal_6022162fb0e58.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468261/normal_604a18917e6ac.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466165/normal_60400dea25234.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471467/normal_5ffe5a1cdcddf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389085/normal_604f9740a83e2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://da18e6a8-d720-42de-a88c-3f13daad7efb.filesusr.com/ugd/08fe48_b87e0e82f9bf4c35991d4af7b66a8b91.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tetofamuxulil/63924040811.pdfIn PDF document text
    • https://bac325b5-3710-4a60-ba01-c1ac5e8a7650.filesusr.com/ugd/c111de_f607e44a8cb44f9d88003e77fac4c1a3.pdf?index=trueIn PDF document text
    • https://f26e6bca-ce10-4524-9610-ed5ef7c8d48b.filesusr.com/ugd/ac8c68_eea294c6228b4071b00ef9a7235aa094.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bulujono/xikutofopodipiji.pdfIn PDF document text
    • https://438c9214-13ba-44a2-8469-a4c97ff43377.filesusr.com/ugd/5d46a0_f553fc5dbb7548d8bf07e80393b1c417.pdf?index=trueIn PDF document text
    • https://b7e73dfe-ad35-4791-b4f7-7500f5b7882c.filesusr.com/ugd/bc79a4_dc9ab5629d084449acfe4bfe736dfdcd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zazelujeju/balance_sheet_and_income_statement_accounts.pdfIn PDF document text
    • https://s3.amazonaws.com/tolivajupeku/97728979668.pdfIn PDF document text
    • https://s3.amazonaws.com/fodose/nfl_week_4_injury_report.pdfIn PDF document text
    • https://s3.amazonaws.com/mulerux/reporters_episode_105.pdfIn PDF document text
    • https://7a69a04d-b0b3-478e-a927-895b34d3dd44.filesusr.com/ugd/159848_817866d1ffac4180b4c0717dcf9a093f.pdf?index=trueIn PDF document text
    • https://944456f3-75eb-4cd6-bbfd-656b3713ada1.filesusr.com/ugd/2c8d66_d6ea2f6961f24edd979b35c407e644ac.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wefadep/16455647754.pdfIn PDF document text
    • https://s3.amazonaws.com/baxegezivumi/mandated_reporter_nys_justice_center.pdfIn PDF document text
    • https://s3.amazonaws.com/fedufiporara/what_is_a_metaphor_in_the_tell_tale_heart.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA29 5000 bytes
SHA-256: 38f1bdbd9f027072e1af71d1a9f0a50f92d4e02dee5fe2d2e96eb3f042bc0b27
font_01_sfnt_off00010b29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B29 11588 bytes
SHA-256: c7ebf6765a6784a1348fa092392452f87f7e1665705530d76d2b8e99e390e6e9
font_02_sfnt_off000132f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F6 16164 bytes
SHA-256: c41fc46809d2260d2d1a821cef6bb00dae560fdbad380da94a93f29d012df54e