Malicious PDF — malware analysis report

Static analysis result for SHA-256 f046bbc42e105bca…

MALICIOUS

PDF

88.5 KB Created: 2021-05-17 17:57:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: be6e0cd56e91c190872ba1d4bd75634a SHA-1: c905569557b57d50fc03c080252662319c94ab68 SHA-256: f046bbc42e105bcacdee394ba9faad6690ba2db0c012955285da7a189543d92e
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded links, such as 'https://pelibifir.ru/strik?utm_term=grade+4+math+textbook+math+makes+sense', are likely part of a link farm designed to lure unsuspecting users.

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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pelibifir.ru/strik?utm_term=grade+4+math+textbook+math+makes+sense PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4481509/normal_5fc6b0c14d8dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413457/normal_6064479bc91ee.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458840/normal_5ff4efb374184.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427282/normal_6041ee4d70fd8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382952/normal_5fec6130e8990.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476001/normal_603047c24849b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471275/normal_6000025b7ffe9.pdfIn PDF document text
    • http://max-lifting.store/delonghi_portable_ac_costco_reviewsr6m5x.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463808/normal_5fd12714f27c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419001/normal_601493a69eee0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503987/normal_604572c3ba781.pdfIn PDF document text
    • http://g2am2e.xyz/womutip9fmta.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427783/normal_6014c8c5ba7ea.pdfIn PDF document text
    • http://trackcreditscore.info/concordancia_exhaustiva_de_la_biblia_strongsfflu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://89511c73-251b-4bee-a1a5-5f4bd4863124.filesusr.com/ugd/f24cb8_d89d9ccd06e94971a207ea06504934e6.pdf?index=trueIn PDF document text
    • https://5366dd3f-28a3-4342-b8e5-5bed86455aec.filesusr.com/ugd/a92322_d79737f0d9c643ec8756fc1a17fc534b.pdf?index=trueIn PDF document text
    • https://e8f98835-b194-42a5-b43f-fe2f29920dd6.filesusr.com/ugd/bf650e_fd6f5479a23e4489adc3896bae728c2c.pdf?index=trueIn PDF document text
    • https://625f08e2-3d8e-45b5-8e8c-b95d001c5c7c.filesusr.com/ugd/d94ae5_699361694aea42eabed4f577c7182cd2.pdf?index=trueIn PDF document text
    • https://52468903-0e2d-47c5-babb-61e1d305d291.filesusr.com/ugd/32777b_5f683562984f4ca4b87ad76776ed5d63.pdf?index=trueIn PDF document text
    • https://a12a05ab-6462-4855-b086-b0a2a961d6d8.filesusr.com/ugd/2c76f4_788a03765ac841a2b737fe0b0cac0dbe.pdf?index=trueIn PDF document text
    • https://8137cd1e-393d-4948-8193-eca935452849.filesusr.com/ugd/756799_93e4600949444616b7b67a71345251ee.pdf?index=trueIn PDF document text
    • https://9505ca4c-dfdc-4941-8fde-ded35496d0c9.filesusr.com/ugd/2097ab_b59720dc11aa49e5bc802a41f3081e00.pdf?index=trueIn PDF document text
    • https://b1e6e3cd-24a2-426a-8b7d-e8f4bd81915b.filesusr.com/ugd/83e584_408738051f35452893a3cbedc38ab414.pdf?index=trueIn 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_off000119a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119A1 5424 bytes
SHA-256: ff304571b18fc93b33b209226150a3b834f6ade8d647597c74190a98cced8427
font_01_sfnt_off00012bf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BF2 11904 bytes
SHA-256: 3415d64e0d9e362fa3d6477c3d87f9311147748ba20fc8ca3df8d4680bb1244b