Malicious PDF — malware analysis report

Static analysis result for SHA-256 15361285903518d1…

MALICIOUS

PDF

85.6 KB Created: 2021-09-15 07:29:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 479611d6b86c6dbeed29a20b5487eabb SHA-1: f53dd1b850d8f85c7e3a8cde3d99aed84765ea28 SHA-256: 15361285903518d180d2d93d77a2f98deca954fae2120b24c966277df1047e6e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, with many URLs pointing to potentially compromised WordPress upload directories. While no scripts were explicitly extracted, the presence of external links and the nature of the heuristics suggest a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://safewatersolutions.in/ckfinder/userfiles/files/65273993196.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/5fd91328bcdc858d5118eec6a0f1c337/37267029891.pdf
    • http://maschimaurizio.it/userfiles/files/82280122518.pdf
    • https://bauarch.bg/files/75232166610.pdf
    • https://girl0229960192.com/upload/users/files/xebamavogutumevutoraju.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/edb8dcc6b1d1ec97fd40037901186d40/falib.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614168792f864---zuxibozesikufepe.pdf
    • http://kemnhapkhau.com/upload/files/35216280639.pdf
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/2820614149.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/48d4101b47acb6045d6620fe4827b267/nofefeg.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613bea7518a2d---madetatuvigirejif.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133a913d8bb3---23245488142.pdf
    • http://kovacsoltvaskerites.hu/images/file/vanivub.pdf
    • https://coil.hk/upload/files/94320872136.pdf
    • https://mytekas.com/UserFiles/file/fokirana.pdf
    • https://robustbrakes.com/administrator/imagetemp/file/38753754693.pdf
    • http://fizjoactiv.eu/Upload/file/93267858688.pdf
    • http://kavernoklub.com/campannas/file/tozireluwaduxuguxiwupuka.pdf
    • http://mweb.cz/images/file/68123441753.pdf
    • https://hr-serdahel.hu/images/file/xezuruwugageku.pdf
    • https://btsis.com/upload/ckfinder/files/wexisoku.pdf
    • https://fenicia.uy/fenicia.com.uy/uploads/files/840220283.pdf
    • http://odontoflash.eu/userfiles/files/savabopelakisikedofed.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=watch+boku+no+hero+academia+season+1
    • 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_off0000e841.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE841 16792 bytes
font_01_sfnt_off00010053.bin
f153428d7fcbab62078694f7856e5178338667f9882b3ee185f3255141f5856b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10053 18292 bytes
font_02_sfnt_off00012f7c.bin
59061c62015be6155800fb691ec15b2054432a58222e00aa01a2d91f4290beaa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F7C 10964 bytes