Malicious PDF — malware analysis report

Static analysis result for SHA-256 a28cf1fc8e141923…

MALICIOUS

PDF

80.1 KB Created: 2021-10-09 03:59:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c126894a4bdfdd37b28306ac07c73f6a SHA-1: b40f680108422d12f80f6fca2620a2fec5027745 SHA-256: a28cf1fc8e1419237d06a1ab913c56725271d5890c18de05b2de2569e0215a01
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to disposable domains or compromised WordPress uploads, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://crewmak.ru/uplcv?utm_term=dirty+look+definition PDF link annotation
    • https://teater77.nl/userfiles/file/nafimawolukowadezumumevi.pdfIn PDF document text
    • https://nieruchomosciturystyczne.eu/files/file/rogezelobavovuxi.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/kuwuxopafururiwed.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/valanimetewesawi.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/48640378100.pdfIn PDF document text
    • http://busto-wl.gattinonimondodivacanze.it/themes/userfiles/files/xofimisatodoran.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/fepibak.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161406ed617def---bibavovewukibewumoxiwot.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/33bc8c3c547c0bbde97f20a8df7d7466/41302356876.pdfIn PDF document text
    • http://www.chubsorn.com/file/files/95340927231.pdfIn PDF document text
    • http://kondicionery-fryazino.ru/upload_picture/file/60792588185.pdfIn PDF document text
    • http://ssp.by/var/upload/kapizol.pdfIn PDF document text
    • https://rodolphe-blanchet.fr/Rodolphe/fckeditor/file/37818994025.pdfIn PDF document text
    • http://strojsteel.cz/webpagebuilder/ckfinder/userfiles/files/40427884176.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/1963genookscbocqsm6551j9lt/47839381552.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/vetuf.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/vivebuwamuxavegevar.pdfIn PDF document text
    • http://inciboya.com/resimler/site/files/dogizadexem.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/kusirubizuwibosujo.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfea858727---fazobusiluvu.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/kajapixubofebuda.pdfIn PDF document text
    • https://senegal4d.com/contents/files/39343265316.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_off0000d53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED51 10224 bytes
SHA-256: 26adb97670e7f0eb33963d006013e9ed4fde4a4fcbc0913b87e822c055b264a9
font_02_sfnt_off00010450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10450 18300 bytes
SHA-256: 587afd49d6edd5c5b9e8861493f6ce0ee8099ed1f9c61dd0fcc9385e1228f77f