Malicious PDF — malware analysis report

Static analysis result for SHA-256 4935f79f0addf94e…

MALICIOUS

PDF

91.1 KB Created: 2021-08-02 02:42:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0f70c7c2cdddf5fac08ff5546a538dc SHA-1: a0a0647b6a435130e3c86b4d1881eda1ffdcdd12 SHA-256: 4935f79f0addf94e5a65c18e1484fcafca63f9b2a11981a91998389469d24940
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised WordPress upload storage, with numerous distinct hosts and embedded URLs. The document body was unreadable, but the presence of these links suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2c5b841e3---vuwilefa.pdf
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/1334e793b2684d40c9b9891290d47ebd/37071756777.pdf
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160742627050f6---xebeli.pdf
    • http://freeski.hu/freeski/file/nunexavudi.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/d185f62b616ef665b795d81f00a57a7b/bivukapaxukosimefi.pdf
    • http://primaria-ciocirlia.ro/media/file/41338603734.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/49641eb145587a11d573f06c5891bed9/xonerut.pdf
    • https://hamzsabegi60szallo.hu/UserFiles/File/908584629.pdf
    • http://cga82.com/admin/File/72632033659.pdf
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/36cb7641dec32050d2865565c1edc4f7/gijesusowekalubuwiz.pdf
    • http://ondrejkocar.cz/img/file/vixuwarolagavegemokiniw.pdf
    • http://www.alfapilates.pl/upload/file/53307520652.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/86753111df89a51f15f719e8de916858/tozawokatuposoletot.pdf
    • https://mayurherbal.com/userfiles/file/loxonowex.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ec7c82be8---76938402963.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2826058da---27022934575.pdf
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/7f0d48e5550ecd6e87b56234afb3a19d/panaxajemesolomerituxe.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1d454f693---gifizukavivimezafenuv.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/9ab6b840c9f9ee19c9d9b60b74bbb50b/40704306480.pdf
    • http://onishi-kyosendo.jp/archive/zeminarumotimuzanexe.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf77f2b3e58---24751671258.pdf
    • https://eobliecky.sk/userfiles/file/11185325966.pdf
    • http://kingnature.ru/files/files/97001947847.pdf
    • https://soft-print.pl/app/webroot/media/files/98395412046.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=what+are+the+classification+of+vowel+sounds
    • 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_off0000f5d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D9 16792 bytes
font_01_sfnt_off00010df0.bin
157178962a43f7b8396b9daee8f9dc9a752da1be3351e7c12a8d61756f55d432
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF0 10816 bytes
font_02_sfnt_off000126e1.bin
2daf7f15f09e093224139ec954ef3d5df4cf53b09517a7721ae8e757dbf08d5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x126E1 22156 bytes