Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4ab465f7c329604…

MALICIOUS

PDF

76.4 KB Created: 2021-09-03 07:24:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1afa1b7db21017e56710b895c3944783 SHA-1: df138bce395d44a9db8d1fbeac4584ddbb0712f4 SHA-256: a4ab465f7c3296048ed8df278ef5d1e9a5d59ae462980aacefe2ff3c83ecdc56
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a common PDF-based redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://ketchas.ru/uplcv?utm_term=food+and+beverage+production+theory+pdf
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/e3hl9b93vkfm0snl4iipf9kvnp/93965717762.pdf
    • https://nenmongdangquang.com/upload/files/85871110735.pdf
    • https://miaousland.fr/ckfinder/userfiles/files/witakosuk.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161085009f1b8d---5879549249.pdf
    • http://odumakus.com/uploads/files/musemojozivapafuvif.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d4db1540520---tiliwafikokorusesebiroli.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aba9722ac82---20441606775.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/77136904606.pdf
    • http://teerosy.com/ipp/images/uploads/files/jiruxifufagapaxogisufakiw.pdf
    • http://rebeccafantarchitetto.it/userfiles/files/bafuzixagobomijutevipe.pdf
    • https://kompaspt1.com/contents//files/93831580185.pdf
    • http://aotwresort.net/ckfinder/userfiles/files/nudura.pdf
    • https://houstoncoinclub.org/FCKeditor/file/20688614335.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/cjoeiu1f3raqqp370ctbe1k2c4/fivetekabupejezuzima.pdf
    • https://soalmatematik.com/userfiles/file/fazotetesu.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e942ccd34e---18867629098.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16094619ad66f8---xiperevixaxunimurax.pdf
    • http://studiogiamberardino.it/userfiles/files/47770074368.pdf
    • http://patanamachine.com/imgUpload/files/lapoze.pdf
    • http://xn--b1agaa2anfqdp.xn--p1ai/ckfinder/userfiles/files/96451988476.pdf
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3177dd7165---saxiduxujekipexawosajol.pdf
    • https://chp-travel.ir/data/file/nunebolegenaxolafusep.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d2ebf3860---47131559847.pdf
    • https://bilalyapidekorasyon.com/userfiles/file/28789084157.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_off0000c84a.bin
dc6873f6a33f9345d464ce93291758d1db45ca0d8394ded1e2363328fc9ff2f9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC84A 11084 bytes
font_01_sfnt_off0000e19f.bin
b745bfc1e0f3b8b18940f4bf1b665c3ecde8ebe6a4ed957f2ac15f12da4497d0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE19F 16564 bytes
font_02_sfnt_off00010c1c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C1C 16792 bytes