Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1987c794b2be432…

MALICIOUS

PDF

76.5 KB Created: 2021-09-18 14:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 209ce366beec22b2742eb9c050376875 SHA-1: 82e9a672fd74d4e0e6509c8c183570774e394c3a SHA-256: d1987c794b2be432337d7af345ea8d9b4f7a0d14330de18c82c06be5d4290d6b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate a 'link farm' pattern, suggesting the document's purpose is to direct users to external malicious content. The ML classifier and ClamAV detection strongly support a malicious classification, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://archism.ru/uplcv?utm_term=excel+save+as+pdf+vba
    • http://machin.kr/userData/board/file/fiwepoxawe.pdf
    • http://abpjseah.news-read.com/upload/files/62089931280.pdf
    • http://80tner.friend-match.com/upload/files/3928307190.pdf
    • http://an-ocn.ru/ckfinder/userfiles/files/65291253566.pdf
    • http://artgrafika.cz/userfiles/file/80181811557.pdf
    • http://harlit.com/ckfinder/userfiles/files/20210917_121820.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c318a3a59---2414968930.pdf
    • http://wojno-stal.pl/pliki/file/49866668659.pdf
    • http://moje-stranky.eu/userfiles/file/rogur.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/04d625a86b05b2bbfaf404b776b1e6b2/72154833111.pdf
    • http://mega-gold.com/userfiles/files/32135884703.pdf
    • http://esrafisek.com/images_upload/files/jidezenirikobitijek.pdf
    • http://gymostrov.eu/gymostrov/userfiles/file/fodolegufetabagag.pdf
    • http://thienlongadv.com/upload/files/18559543538.pdf
    • http://jobcred.com/rk/jobcred/uploads/image/file/49219208432.pdf
    • https://goacetours.com/ckfinder/userfiles/files/vobofusabogubinovat.pdf
    • http://mintaialuminum.com/d/files/wujukokadusudemudowibe.pdf
    • http://www.ags-sib.ru/ckfinder/userfiles/files/93106394777.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16141c0a580ea7---92941945335.pdf
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/vobakevegomonefulawas.pdf
    • https://steklo-shik.ru/userfiles/file/vinuninimegoxuvefelo.pdf
    • https://pernambucoimortal.com/imagens/files/34303462646.pdf
    • http://fcvperu.org/data/fcvperu/userfiles/file/numabokatekoluger.pdf
    • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c82d.bin
188016ff857d2686e8cad01cf75d8ce56619bf7250803218213391cda78748ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xC82D 17384 bytes
font_01_sfnt_off0000f52f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF52F 16792 bytes
font_02_sfnt_off00010d46.bin
e598196126071433c93d8750df0b63705ca7063862fd1433bfc570500ba5e654
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D46 10392 bytes