Malicious PDF — malware analysis report

Static analysis result for SHA-256 4437820fe246f27d…

MALICIOUS

PDF

84.8 KB Created: 2021-03-21 23:26:38 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 008925b9ecfd1f7a0b4f15d0601f988c SHA-1: d89642066862d0ab3b48be98b56a9daf37b02c38 SHA-256: 4437820fe246f27dca598198ba1ce0e664e702a12af331109cb4081acc204f3e
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains numerous embedded URLs, with one specifically identified as an external URI pointing to 'https://jottigo.ru/award?keyword=catholic+theological+books+pdf'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is part of a link farm hosted on disposable domains, further suggesting malicious intent. While no scripts were explicitly extracted, the presence of embedded URLs and the overall detection profile strongly suggest this PDF is designed to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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://jottigo.ru/award?keyword=catholic+theological+books+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4499021/normal_60472e9eea45f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478148/normal_602b04ecb55b4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378425/normal_60109317bda88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368249/normal_6032a6cc9872c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369643/normal_602071333f899.pdfIn PDF document text
    • http://zomesotemaxage.66ghz.com/tugibipa.pdfIn PDF document text
    • http://vugadabupujexax.22web.org/wilefotiserevujerom.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465257/normal_602c5a660658c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458829/normal_601e0d36c63a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372377/normal_5fd391674f649.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381740/normal_603c50551958d.pdfIn PDF document text
    • http://gulexamotapa.iblogger.org/73007533516.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403537/normal_6053a05892806.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
    • http://sivumokevidosib.rf.gd/repukozuwewitotove.pdfIn PDF document text
    • http://fokodema.epizy.com/breast_cancer_information_in_marathi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06f0d560-8ffb-4890-9291-f5ea0827d2b7/98816538183.pdfIn PDF document text
    • http://guvewenif.epizy.com/xamakebosimos.pdfIn PDF document text
    • http://gixopesibesuges.epizy.com/75688442104.pdfIn PDF document text
    • https://s3.amazonaws.com/zafirawit/video_5sos_amnesia.pdfIn PDF document text
    • http://wujawejibizub.epizy.com/fizogopojuvapidetokizavak.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/32080c8a-f00b-4229-97f4-64c9c067d944/glenfield_model_60_recoil_spring.pdfIn PDF document text
    • http://fuzaxovojige.epizy.com/ffxiv_leveling_guide_30-_40.pdfIn PDF document text
    • https://s3.amazonaws.com/simujix/how_to_fix_e4_error_on_ge_dishwasher.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/added829-d481-4e30-893c-ff932ded84d8/jegubogekugenelazafaber.pdfIn PDF document text
    • https://s3.amazonaws.com/janodojivi/45601351755.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_off000100ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100AC 5232 bytes
SHA-256: 69ce1406dd235d09c4dfb3ad53bac26b932d87a87cc8a15c1ff2d29e35a2a194
font_01_sfnt_off00011286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11286 10980 bytes
SHA-256: 55bef1932bd0fc594bb63fd8a68034a99f98ca1b7cb6704b634c1743f8b4a1bd
font_02_sfnt_off00013796.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13796 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3