Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c81188498bc22e…

MALICIOUS

PDF

120.6 KB Created: 2021-03-26 08:21:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1d0aae057b80a650ab87989668dad1c6 SHA-1: 79c00598b9fc6ea695247cbb87f026950b7d7832 SHA-256: b5c81188498bc22e98266baae5c19ba70f1d838fe759d781b371110ca6a8a83a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly suggests maliciousness. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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 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://jumiwimov.ru/wix?keyword=%25D8%25B5%25D9%2584%25D8%25A7%25D8%25A9+%25D8%25A7%25D9%2584%25D8%25B9%25D9%258A%25D8%25AF+%25D9%258A%25D9%2588%25D9%2585+%25D8%25A7%25D9%2584%25D8%25AC%25D9%2585%25D8%25B9%25D8%25A9
    • https://xasigali.weebly.com/uploads/1/3/4/3/134363336/nipobixedevutesi.pdf
    • https://gomafaned.weebly.com/uploads/1/3/5/2/135296522/xixatutizuwum.pdf
    • https://newavutija.weebly.com/uploads/1/3/1/8/131871734/3883935.pdf
    • https://zaluzukefajol.weebly.com/uploads/1/3/5/4/135400247/c572d477e2d9.pdf
    • https://cdn.sqhk.co/gudopokobipa/eiaAgd2/73464464717.pdf
    • https://gupijevud.weebly.com/uploads/1/3/1/4/131407369/kutalodiw.pdf
    • https://cdn.sqhk.co/vuvupewog/o5RibHy/most_popular_tiktok_songs_august_2020.pdf
    • https://cdn.sqhk.co/saligoliti/djjB9gc/lorivifovesarimivijagixi.pdf
    • http://retapadu.medianewsonline.com/roland_td_30_hi_hat_problem.pdf
    • https://cdn.sqhk.co/gipudeviwapi/4ghwjiT/deliw.pdf
    • https://wepubimixojipo.weebly.com/uploads/1/3/4/5/134584552/3eb2e8b42cfd08c.pdf
    • https://wubigunes.weebly.com/uploads/1/3/4/5/134507070/dukivejusag.pdf
    • https://cdn.sqhk.co/rasepotobami/wTjd3hh/99599780396.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://bumurulepowele.myartsonline.com/bringing_in_the_sheaves_chords.pdf
    • http://nejarisiwudu.atwebpages.com/25356097580.pdf
    • https://677f84e8-2a3b-482a-8721-58d714100356.filesusr.com/ugd/086aec_75e29ecfa0154e3f8eff8e8e467b615f.pdf?index=true
    • http://dotopaku.atwebpages.com/labomazuxivomikoxulemefuk.pdf
    • http://taberadajip.atwebpages.com/kixexiwiwurix.pdf
    • https://ca108e69-7b6b-43f0-8f16-d96ebeb8a33d.filesusr.com/ugd/79e0dc_2117596fee0044e89ddd09d58049c01a.pdf?index=true
    • http://pasifowon.atwebpages.com/xosokubinudujilisavesut.pdf
    • http://zevusup.atwebpages.com/how_hard_is_gre_quantitative_questions.pdf
    • https://2061f665-9309-41a6-981d-137229ee7e60.filesusr.com/ugd/eb2fe6_2dca4d0cc36a402bbbb74979d329f69a.pdf?index=true
    • https://1ceef7f3-d523-4f80-a0a4-3aed54d3d17a.filesusr.com/ugd/48841a_25c3e3cb1a064f0db21008846f679d39.pdf?index=true
    • https://6e229dea-1f83-4be8-8cd3-388eabd4f5e3.filesusr.com/ugd/1cfe37_fc0a3c884e524ad1956a1c7ee20dbe92.pdf?index=true
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License
    • http://scripts.sil.org/OFL

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_006_off0001963f.bin
39e3b8ed9461dc39491ed026bfd7c816ee167f92a85102278a7e5265f3777966
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1963F 34044 bytes
font_00_sfnt_off00014c6d.bin
8d54ba483edcd39216d400a53fba213e807fef755950b553a37a312b28b6de65
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C6D 4068 bytes
font_01_sfnt_off00015a4c.bin
764f449de5ea1d547b6faa3ee1b886d9eed76a859fc24599976e0c2c79364484
pdf-font-stream PDF embedded font (sfnt) at offset 0x15A4C 9508 bytes
font_02_sfnt_off00017b28.bin
b3d1ffa3de5b9519bcc9c93ae682d4f84d071ded34037a2ecb943e99bae3e9c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x17B28 17772 bytes