Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cd608e96f992d34…

MALICIOUS

PDF

76.9 KB Created: 2021-07-08 00:25:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3c951dfc911486f263b60eeec62b2e4a SHA-1: 4a12ce8eee9ee53a516b66f343cbc6cf91af88a7 SHA-256: 9cd608e96f992d3421f189273fa896d5920b41cc7fdaf909c8b7c6e03f557787
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites and other disposable hosting, suggesting it functions as a link farm to redirect users to malicious content. The PDF structure itself does not contain readable content, but the heuristic firings strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://ecovn.vn/uploads/news_file/fexotumikomukuwumowubax.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/841573f756c317224197252b91d7af2b/bivadokek.pdf
    • http://www.hangmandigital.com/files/file/68657029320.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcfb7b75754---jazosumud.pdf
    • http://fluitec.fr/ressource/site-image/files/93260533472.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16076efca6927a---zugadevadud.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a20dc092126---72227080783.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/acecef0282b4f2a9b8ada1300080bce6/zomiberita.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608914e58d0d9---daxapa.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c84c42d643d---wixaturuboxediripuzuzu.pdf
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c7646300b---97406183866.pdf
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/c06c2efb096058b3fd2ce3bb734cd026/roduwopilewalejejuvogu.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9eb532253---7643687860.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f9aa17e42---5578689725.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/dubalaruz.pdf
    • https://oversaslogistica.it/file/7128976540.pdf
    • https://ghnservizi.com/file/72531608522.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/k3ulj8bj2jn2ciep4up1nfqcfc/35890197606.pdf
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/27u93k9bcu3l7u6sm859dtaib0/11110644510.pdf
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a94f891583---guwolesikimapesaresexax.pdf
    • https://ewastexperts.com/userfiles/files/59401749300.pdf
    • https://senfina.top/uploads/files/lunijunavuxidegomuwalib.pdf
    • http://infrabud.eu/fckpliki/file/93641700206.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c830a0bf3---76746299639.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=the+private+life+of+the+brain+by+susan+greenfield+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_off0000c994.bin
df4cfba947fb657aa96c29db25e8e4a50188000fca4139e7815e3104ef14d9d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xC994 16364 bytes
font_01_sfnt_off0000f40f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF40F 16792 bytes
font_02_sfnt_off00010c26.bin
0918c773c7a580703a10a115b6ccc416a2a2a0be785978845d051e1e53b7a24e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C26 11160 bytes