Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e3f3b86c4cf5972…

MALICIOUS

PDF

76.0 KB Created: 2021-06-30 06:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9257caad72ce0e84e30605c48671ff2 SHA-1: 4da74b84592af30d1b45361137730e4726e8d16f SHA-256: 0e3f3b86c4cf5972682122c7e595ebe80818f2748110559661efb85607d4c7ee
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting, designed to redirect users. The presence of multiple external URI heuristics and the PDF_SEO_DISPOSABLE_LINK_FARM firing strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://wodepcb.cn/uploadfiles/files/jenozozirigidizofuluwopo.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609832db61488---winutodeladozitemev.pdf
    • http://diagnosticaedilizia.com/userfiles/files/turul.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090a7602a8ef---walotupajur.pdf
    • http://grandinhr.eu/images/user/file/gulumagiwu.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/dca9f7aa3532065838bd44396349e767/49641861419.pdf
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/dj4s5nqg4mm9m8cls7f2crjhgp/89534710002.pdf
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/09535b8464d58b6c9ea3411a795b10a5/85879407550.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5940c0da0---31489365389.pdf
    • http://schmetterlingsgaerten.de/file/malez.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160812e79364a8---42388228130.pdf
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/figosidagoxufosanorirok.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/75804e71adde7ad9ee5a34099806ff1e/10271931435.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160833bf2eef07---89423427911.pdf
    • http://prattsofdouds.com/clients/d/d8/d85aab9f4bcbae69c8358f7a9990a0b1/File/firinavugaguwabes.pdf
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088c8e79ff37---fobimutolafilir.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf04bd5a1cb---34625836890.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608925cfeb340---67786840820.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/f5b3e7fbfbd4054f21cdc075f8d47977/palapalixow.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160c7c134c8d9e---98753123966.pdf
    • http://allmedicus.com/userfiles/file/27544581167.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083c619aedc4---51079373823.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8e386beb1---xifewulafug.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=1200+cm+to+m
    • 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_off0000c8db.bin
1a464203ddabeac5016647c765907fe50d71b081388bb9fb3e36394384a48ab7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8DB 17320 bytes
font_01_sfnt_off0000f5c1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C1 16792 bytes
font_02_sfnt_off00010dd7.bin
23696935894711ba2eb216928348a1ac46d91b7f4f37392638a63f7b17785836
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DD7 9784 bytes