Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4b9a5c283bf0171…

MALICIOUS

PDF

70.3 KB Created: 2021-09-03 02:17:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3e2d1a9e95e1262d8a30a7255ad298c2 SHA-1: 38159637b897481fec1a86cc8545c12bebff21c1 SHA-256: f4b9a5c283bf01713bb983dc10b37b72c8b08a54988b5626f51b87d598dbb1df
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a link farm designed to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of a link farm on potentially compromised or disposable infrastructure. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or scam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • 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.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/6c5j4e3hnoutaps88ls7p03r4m/gekukagonenirovodaz.pdf
    • http://eskuvoiiranytu.hu/blog/file/77356393869.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/e583977fdb9b6191a325a24fa35cbdea/felupuwidavakexuna.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c927a370eba---gujatibidofar.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e50eacea0---xasukijepe.pdf
    • https://landatur.com/files/galeria/files/lubixofonuzagutu.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46be327a9a---numebubujoxak.pdf
    • http://shriadinathbank.com/uploads/43305729795.pdf
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/f5621eb6822468638453b165372d7701/najipatojumulobosezoba.pdf
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a505a0cf4---boxilufo.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/1f5d8139c0a6a45b3d496d2e0418da7e/19551311997.pdf
    • https://transport-vehicules.fr/userfiles/file/fovabitema.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/da283dd52f5955f9e4a7fa3a57c11e4b/fejinokitovuro.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160837c80e0b4f---48562899264.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/e8718f7270b894e737dcbf66dca33e16/27666427578.pdf
    • http://vswet.ru/f/70701558766.pdf
    • http://zuche0551.com/upload/file/91417305909.pdf
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/3ecf9d504cd1ce0ada8b2b3feead45ec/difunubonizumixofamatexu.pdf
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d955ba17b55---robimovijuwafisa.pdf
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/c61c558d38840f424de4b78f20c7d660/39602901244.pdf
    • http://arlingtonhigh1959.com/clients/863184/File/kerobunaduno.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609849657cb5e---54565021592.pdf
    • http://www.uc-kushiro.net/images/library//File/jifonojupulamibosifebi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=surt1000xli+service+manual
    • 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_off0000b78f.bin
a5fd5d8fefaef2c9d48ff5cd792e7405dab809a9813745fd1828f08ccc018b28
pdf-font-stream PDF embedded font (sfnt) at offset 0xB78F 14268 bytes
font_01_sfnt_off0000daf1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF1 16792 bytes
font_02_sfnt_off0000f308.bin
a4ed449d844269f2025308a32121a8ae0e98c6cc333d9278b2cb2ff17996f77e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF308 10788 bytes