Malicious PDF — malware analysis report

Static analysis result for SHA-256 2733825b7e382039…

MALICIOUS

PDF

72.9 KB Created: 2021-10-14 11:46:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 1aeac8dd27251d654df116927c6ade6d SHA-1: c500227796f42abf95e6670508b5243420a689d3 SHA-256: 2733825b7e3820396ecf5ae08053b2eb0615a1c2b91dd3a6027c0470dfeefcd6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to disposable hosting and compromised CMS uploads. The embedded URLs suggest the document's primary purpose is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://queure.ru/uplcv?utm_term=grid+autosport+download+for+android PDF link annotation
    • http://music-summer-courses.eu/upload/files/gavumevofobusirot.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/25cd062441ac529bcfb4ee1cba0c1d2c/82282994354.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/xakubosig.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/444672627.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/gepadevexu.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/62854589297.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-10-10/20211010071546326219.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/mekovivo.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/rexawe.pdfIn PDF document text
    • http://agilesolutions.in/uploads/41444778082.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/d7dd5d7738381527e9de3e3503b32af4/46564605402.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/dadosizuwawawabisapobibaw.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/lolowovo.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109021104253734.pdfIn PDF document text
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/72264608004.pdfIn PDF document text
    • http://katachizu.com/img/news/files/59989339493.pdfIn PDF document text
    • http://vhshf.de/File/sanuborowikut.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/63889824128.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20211008193058357958.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ae3395d0c337109299e23db3492963dc/pogekoze.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/tegibupezafalivugemovul.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/3000502493.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/tiwufudut.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://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_off0000b70e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB70E 10584 bytes
SHA-256: d38089355e5f740af76eebcb785efacb5aa0b48514fee7788e4cbba5c650af08
font_01_sfnt_off0000cf69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF69 18084 bytes
SHA-256: 075dae0a00040ba94632d9a8315709d15d9e1ec1cddb5283b55152b6497e26a6
font_02_sfnt_off0000fdf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1