Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab266336e478b141…

MALICIOUS

PDF

79.9 KB Created: 2021-09-09 18:10:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: dd4692e4610c88f1181be0a4d9ce24af SHA-1: 578829fb8fa482907c8243adde6f3f6e2609f08a SHA-256: ab266336e478b141909943d3336ce1220637a0d9a3a97e9e2fce3b0f8395e73b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier. It contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a pattern of using such sites to distribute malicious content or redirect users. No scripts were extracted, but the PDF structure itself is used to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • 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.
  • 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://oniceh.ru/uplcv?utm_term=vidmate+app+live PDF link annotation
    • https://lyonsinn.com/nbloom/fckuploads/file/29974492470.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/19116325876.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16137a1e1cce20---nukavoweko.pdfIn PDF document text
    • http://traktor-tv.de/sites/default/files/file/kexukaruvojisujojud.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/85262852115.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/40552528356.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/tekosoxinisexovusam.pdfIn PDF document text
    • http://nattukoottam.com/userfiles/file/78054477327.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/56295881929.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/50223448643.pdfIn PDF document text
    • http://rassadaspb.com/new/files/file/tunigujisegubadafegeket.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/44912603856.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/fe5j030c6tegsutpla036du4ma/tozugeki.pdfIn PDF document text
    • http://sladkiy-ostrov.ru/userfiles/files/66642203846.pdfIn PDF document text
    • http://www.radio-kum.si/data/files/70862204289.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/purelokisazab.pdfIn PDF document text
    • http://polipack.ru/content/file/fademazemururul.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/mifojezutolatodufa.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/6033282438.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/f317eb104172b74199fdc946e2f09bec/1714556329.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/runogajel.pdfIn PDF document text
    • https://podereilmontaleo.it/writable/public/userfiles/file/28243124276.pdfIn PDF document text
    • http://makesomenoise.hu/upload/file/93935956472.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_off0000d663.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD663 10096 bytes
SHA-256: 9220f83c386bcbf3c99a03b3e588c5b632158c2ef6f3ec45068a7d19024bad68
font_01_sfnt_off0000ecda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECDA 17840 bytes
SHA-256: de7059863a66c852fdc461d8d9d1c3d12612c42c66ab38e423d6752b32396f07
font_02_sfnt_off00011aae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1