Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9ce2629241ec154…

MALICIOUS

PDF

90.2 KB Created: 2021-07-18 02:46:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 469beba6dea397e3cd4940e1398c1580 SHA-1: 0b35e41b233378674e802ced1369b88e81fd493b SHA-256: e9ce2629241ec1545ecd8d87d1f660cf08e234c25ff3ac1bfa7a0ccfcd8dc119
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress sites and other potentially disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://world-housing.jp/ckfinder/userfiles/files/mutakafiwi.pdf
    • http://salt17.com/userfiles/files/pamuwowodawemubiroxa.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2ec2202ea---87194864914.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dec1cef48b---85210654228.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b614737e43f---bifeloreredixomukaxivuf.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4af65bde91---17068964938.pdf
    • http://soles2walk.cz/data/file/55623060368.pdf
    • https://deshpanday.com/ckfinder/userfiles/files/70174237683.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/3e65713d695cbee7f1e09ffcd2b58ab1/pobutilaziwofibekesojipe.pdf
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/22f5fcbe2c1ce73eb649357c7858c759/folenukeluxutotonot.pdf
    • https://abugfreemind.com/userfiles/file/25954986511.pdf
    • http://kelvista.lt/images/files/turudomobisakemomugozoxo.pdf
    • http://metrocars.london/survey/userfiles/files/nukunobazisesi.pdf
    • https://arhometutor.com/userfiles/file/61946357199.pdf
    • http://vnndt.com/Images_upload/files/zuvilejunomitilul.pdf
    • http://yangs-ns.com/ckfinder/userfiles/files/20210605004749.pdf
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4e1a36a8a---bejawonuno.pdf
    • http://shukokai-voves.fr/userfiles/file/toviwojaxupodusalisobapel.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/43326c5eaaef3011b51f89c3fecd72c7/73292359954.pdf
    • http://erbamedica.org/userfiles/files/69147422419.pdf
    • https://adsbudget.net/userfiles/file/titomififuwofidiwo.pdf
    • https://nusamulticentralestari.com/Uploads/userfiles/files/xibesawu.pdf
    • https://prokoncept.hu/admin/blogfck/image/file/90845395245.pdf
    • http://currycornersugarland.com/admin/images/file/11288938649.pdf
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/ca3d642d48e71859b0c390844163373d/76357616588.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=a+streetcar+named+desire+main+message
    • 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_off0000ff92.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF92 16792 bytes
font_01_sfnt_off000117a9.bin
b46faed32f71b5df3c32bc695c016641e083d2313088668530e4713f295f9f4a
pdf-font-stream PDF embedded font (sfnt) at offset 0x117A9 10528 bytes
font_02_sfnt_off00012f70.bin
c9d35942d7d361552d31f0c984e5105fbb82f33d84493626b1d0860dded2b877
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F70 17228 bytes