Malicious PDF — malware analysis report

Static analysis result for SHA-256 e0e855a26b40ecb1…

MALICIOUS

PDF

117.0 KB Created: 2021-06-27 12:01:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa74b023b80dbd797e6361f9f37ab2b0 SHA-1: 14c937829c4721e321bb7e1c8b5de7062faf8be9 SHA-256: e0e855a26b40ecb107a47e9263b3a6958863a02776a0ed9cc5c499915c522a71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous external URLs, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. No scripts were extracted, but the PDF structure and URL patterns are indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://wastran.ru/uplcv?utm_term=theory+and+calculation+of+heat+transfer+in+furnaces
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/826602a5a1e9acaf68782b58ffdaa7e1/jirulutepojovakanozowol.pdf
    • http://debandhelder.nl/ckfinder/userfiles/files/10038804478.pdf
    • http://polymer-optix.de/userfiles/file/30434226829.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/79lv2pirs4d13mbudapp4a6p8a/mizodafufoxari.pdf
    • https://myphi.biz/nbloom/fckuploads/file/16220735301.pdf
    • http://bakoca.hu/files/file/40999464505.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/bb3892c3f46371cad64063d4ad769ec2/62093764771.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cac75b240b---lumaz.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/f46133e4a23d2a046d797b36cf983125/zefapukomibonofifobu.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/e20a77f50f2f7fc65ec61bb3fb56e00e/88332808709.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb478cd6924---3118835902.pdf
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/sodigaze.pdf
    • http://border-inn.com/CKEdit/upload/files/zojaxutosivobikatavajepu.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b02e5350450---10199490694.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/666041603a6d1228256078c0101fd47b/folipukit.pdf
    • http://lab4050.com/upload/editor/file/20504571622.pdf
    • https://dbjadow.pl/attachments/file/47541131210.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b26bd7a0ff9---nulozegowijamipitewavonib.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a139691616a---zemasopema.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160962541d15e8---2062325697.pdf
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/dubncetvmqu6qh8bksqqbugpr7/42063777523.pdf
    • http://voszveszprem.hu/_user/file/10838562007.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6d240dc745---82206348679.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/3e8ea4d82f4a192399ea648f60bf040e/zimugenagenifirunikageku.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1608c699c44d73---57802059640.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_off00016779.bin
6858b2c717776417cc03acfe2f8686b77011acf1d7e39bc34a973b96d01da334
pdf-font-stream PDF embedded font (sfnt) at offset 0x16779 10752 bytes
font_01_sfnt_off0001802b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1802B 16792 bytes
font_02_sfnt_off0001983d.bin
6503e021cff8a495e17f52cfe171443426d38718152b80c2c803befe77f2ccf6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1983D 16820 bytes