Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b35a74e42af6353…

MALICIOUS

PDF

89.3 KB Created: 2021-09-02 07:03:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 92cc615e4643565153c6cd326858cd22 SHA-1: 330cc2cff2bd1f3c219ed9f2ebb60ac30b9c4a42 SHA-256: 4b35a74e42af6353610063e5e203563905558d50acdbbe1047386a30933067c5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that act as a link farm, directing users to a variety of websites. Heuristics indicate these links are on disposable hosting and potentially compromised CMS upload storage, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://catamma.ru/uplcv?utm_term=roof+construction+types
    • http://ergo-logo-bamberg.de/userfiles/file/sutozowumonilogo.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9d3553142---38721258253.pdf
    • http://hdurmuslar.com/images_upload/files/kovatonot.pdf
    • https://hfbee.tw/upload/ckfinder_temp/files/20210809032425.pdf
    • http://xn--90aoa5aj.xn--p1ai/ckfinder/userfiles/files/52173530473.pdf
    • http://bonfiremadigan.com/uploads/fckeditor/file/jedula.pdf
    • http://tokyoracing.hu/userfiles/file/29175865863.pdf
    • https://ietc-oman.com/userfiles/files/jexur.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe789a5bef---12587915590.pdf
    • https://dalton-english.com/userfiles/file/sefapenosej.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/5f98c9ab7a5138bea5d882caf6e2aa42/77957074985.pdf
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/6072b4a71bb44b6faae5730007ea1527/batapepuzojexusokogi.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a843b9b159---pulumanodomisab.pdf
    • https://alnahamgroup.com/userfiles/file/31741690469.pdf
    • https://sentinels.ro/userfiles/file/67911511205.pdf
    • http://aguito.madteam.net/ckfinder/userfiles/files/24324266612.pdf
    • http://bagliodeimille.it/userfiles/files/68944994052.pdf
    • https://rachelrom.com/rescontent/file/labudetebed.pdf
    • http://custom-mugs-factory.com/uploadfile/files/bogejevesonokorokib.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa1dc7dab2---20085044838.pdf
    • https://aawyx.com/sites/default/imageuser/file/40614000445.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb50e30a0e---9172250689.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/8e2f49002419832a2e800e1104d49b12/lexunedabobodekufepinijul.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a448e0ddb---94175607404.pdf
    • https://licorne-hotel-restaurant.com/userfiles/file/2452536882.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c98f81eb8b3---76839192700.pdf
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/93829cf8eb4ce2c00907705f94ecf46b/56120365267.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_off0000f67f.bin
5df83690fc9fa6fb4d16a29aefedff5d0cb9c68616a1f3e1f0746472938e4301
pdf-font-stream PDF embedded font (sfnt) at offset 0xF67F 10524 bytes
font_01_sfnt_off00010ea6.bin
eb96a1648d16244f56028f6f1167117ccd82ea890aba91be75c7cfb7283df6ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA6 18684 bytes
font_02_sfnt_off00013f13.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F13 16792 bytes