Malicious PDF — malware analysis report

Static analysis result for SHA-256 881ee0ffa98df6ed…

MALICIOUS

PDF

87.0 KB Created: 2021-07-24 15:01:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7d89059aee744ae18e177e19243552b5 SHA-1: e1eb8f74fa615bea9ccb34150fa66b837d658ad3 SHA-256: 881ee0ffa98df6ed5bef9d6333139b059ac53de9af62973561dd15dbee5a7ea7
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1553.005 Security Software Installation

The PDF was flagged by multiple heuristics and a machine learning model as malicious, with ClamAV identifying it as a phishing trojan. The document contains a high number of links, many pointing to compromised WordPress sites, suggesting a link farm used for phishing or malware distribution. Notably, it includes an instruction to disable security software, a common tactic in malicious documents to facilitate further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • 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://studiomontironi.eu/userfiles/files/mekonuvo.pdf In PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/c7c728d327319688808cf8de49e18c34/vuguvisexode.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/kesaviburazo.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1b0a6ee7a---61973339230.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca45ece951---wozikobixu.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/15c7bd177c57f361c5f63ed78a791bf0/82318946314.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/jerisupilupojop.pdfIn PDF document text
    • http://cuatudongsaigon.net/uploads/files/kiwizegevapam.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/8c08m26nhd202lc6dfl6qaeme0/15601988005.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/617tu68g3hjs7gvbs601drbv10/fedakakubateropomopapisi.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/84277882892.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/717e793466b886b8caade0b89f4a9e2e/retunovunogutune.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/lexenedupesup.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/namofoxupezozuxepiv.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/17998361759.pdfIn PDF document text
    • http://johnsonsdynastyincfamilyassociation.com/clients/10108/File/16686527258.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/000574a4eb484bd0d76d5ab220f045c1/xatokiwirug.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/pfkt5055av8v3rn9djqng0jsf4/rabeleguletonazuxivaniva.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c087a8be0fa---67890900717.pdfIn PDF document text
    • http://china-miyaco.com/img/file/2021621132548.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d7a648cc2---dimoxejupak.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/16084a18279806---3343474904.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/ed7078470a7b8a27ef69331071fc05e2/jaxaxek.pdfIn PDF document text
    • http://lineshare.net/upload/files/20210703090506.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/nit29qdcbslt3g5kdnc2ecimag/gerapakivagiwagokivufe.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/13021599878.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=z3x+samsung+tool+pro+36.1+crackPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010487.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10487 17868 bytes
SHA-256: 0115684f33f465c10ef8ed15117f074ea0cb47a19f2bbe3778d99781a2064cab
font_02_sfnt_off000133ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133CA 11208 bytes
SHA-256: e47ac399276e96caf002235130b0a45b4b8890f40a67fc2e0e0749c00c4872ee