Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cdcf3129457b45b…

MALICIOUS

PDF

89.7 KB Created: 2021-03-31 12:48:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: cfe4e9b18e460fce7f15b09da23de65e SHA-1: 85413065b681d47ecd9c952dca254e0701749c7c SHA-256: 4cdcf3129457b45ba8ba18d0faf9fe12874fce1460a50c5007b66e5c43aec82e
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards an attempt to exploit users by directing them to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://soxebez.ru/123?utm_term=reporting+kruskal-+wallis+h+test PDF link annotation
    • https://cdn.sqhk.co/letarezetap/CDWhbqq/bamogapewinifusofenarilog.pdfIn PDF document text
    • https://wivixape.weebly.com/uploads/1/3/4/8/134897282/kinax_zewerosemo_xijikekejep.pdfIn PDF document text
    • http://tubujefowabe.medianewsonline.com/chlamydia_trachomatis_traitement.pdfIn PDF document text
    • https://pozemake.weebly.com/uploads/1/3/0/7/130776760/sejopos-bebagom-kogabilap.pdfIn PDF document text
    • http://damewumesigalut.medianewsonline.com/wovukaluxolizaz.pdfIn PDF document text
    • https://cdn.sqhk.co/vofosutuwo/jaibCjd/35069070432.pdfIn PDF document text
    • https://wamurereleveti.weebly.com/uploads/1/3/5/3/135392703/4813464.pdfIn PDF document text
    • https://matiposokatogu.weebly.com/uploads/1/3/0/7/130739068/5201c2.pdfIn PDF document text
    • https://cdn.sqhk.co/zabeluzitema/rUsijlm/12688445438.pdfIn PDF document text
    • https://xoxumowuna.weebly.com/uploads/1/3/5/9/135964844/aaa9ed8e0e13e.pdfIn PDF document text
    • https://gepadagonuvo.weebly.com/uploads/1/3/0/7/130775626/suzemobi-sekazivomirud-barin-zogebulusekadi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://07d68bf2-0661-47e2-9ffe-eae068a071af.filesusr.com/ugd/fef806_b0c9a9e6f67549fd8d1714e64090fff0.pdf?index=trueIn PDF document text
    • https://6eed613e-cbae-405e-b458-9655ef9033f8.filesusr.com/ugd/e4f6f0_9ff39de02d654a609d3b71e5e0a08722.pdf?index=trueIn PDF document text
    • https://60659a61-a27b-47ea-8eac-a81775c62269.filesusr.com/ugd/7a7fb1_bfc503a919b04646aebc4255c4be1791.pdf?index=trueIn PDF document text
    • https://57fc24c6-ba7c-430a-bdae-05304608b610.filesusr.com/ugd/bc9c68_105104d5dcad473d92afc674d4396405.pdf?index=trueIn PDF document text
    • http://desovizipelo.onlinewebshop.net/mupenuk.pdfIn PDF document text
    • https://1ee34b3e-bfcb-4e25-b227-79ffd44eef10.filesusr.com/ugd/9d5096_6c40ab49fa4f469caf23124de902ee4f.pdf?index=trueIn PDF document text
    • https://dd907c4b-492b-4b4d-bf3c-9f0b7a2bd2c7.filesusr.com/ugd/96a426_672f4d90a67340c2adafef5ba18721a3.pdf?index=trueIn PDF document text
    • https://48e5b1ff-25fb-49a4-826b-3ad3f3a15688.filesusr.com/ugd/0d632a_6ac694f795a64876b5b2cc69a89d7f97.pdf?index=trueIn PDF document text
    • https://aa3bb5c3-2bd4-4791-9e2a-6e31d5009b04.filesusr.com/ugd/60e703_07e698deb80a4b58830ae10c23c3d5a5.pdf?index=trueIn PDF document text
    • http://wepunulirepobi.myartsonline.com/cdna_library_construction.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_off000120d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D9 5276 bytes
SHA-256: 565aa313afed4ed6ebfb6bfeef3e11eeca8f815fbcfc570e745fc7b0fdebe426
font_01_sfnt_off000132e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132E8 11576 bytes
SHA-256: 7914db33cb18e4f68bdd5f7b05a754210347c2e593e0203152a53ca54569dc67