Malicious PDF — malware analysis report

Static analysis result for SHA-256 a07fbf17ee42aa57…

MALICIOUS

PDF

70.6 KB Created: 2021-09-26 08:23:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: c82c54b8652908da03661fd8e18a6b52 SHA-1: fa1da1c600e3a18c8e129b58b45560843e674b3c SHA-256: a07fbf17ee42aa579dbcba9635336d862250c66481d18f753fe5db3785041f5e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF's primary function is to act as a lure for further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://infrive.ru/uplcv?utm_term=android+azw+reader PDF link annotation
    • http://webs123.com/userfiles/file/23345995135.pdfIn PDF document text
    • http://leton.pl/userfiles/file/66011831532.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161307dac02416---45063808213.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/kuneniwa.pdfIn PDF document text
    • http://rubella2.integra-sh.com/userfiles/file/niwozoguwesebutajonoli.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/kijolokaxofotewupamutezi.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/9986395837.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e3cf051ba---13794082632.pdfIn PDF document text
    • http://criminisiepartners.it/userfiles/files/7580123999.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/18924649720.pdfIn PDF document text
    • http://egyptlance.com/userfiles/file/samurum.pdfIn PDF document text
    • http://meetburgerusa.com/uploads/files/33403218102.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/jatutirabapijiwimoxak.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/gefosevuweragavekubulev.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/01114634a16fc144c2ae43c32548ef5e/pigoxek.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/44848472181.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/5073d0f72486c350ff206c122df36d75/nabasoxevuselelamukopep.pdfIn PDF document text
    • http://gizmakina.com/depo/sayfaresim/file/gugiziwusalasumarobodo.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/60451758789.pdfIn PDF document text
    • http://righetti-ticozzi.it/userfiles/files/sexevub.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f08330631e---golik.pdfIn PDF document text
    • 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_off0000b079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB079 18128 bytes
SHA-256: 56c48289e7a81e7153e35976df19ff0e0ce84e9d2104a513b8201c43fc8a8456
font_01_sfnt_off0000ddef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF606 10056 bytes
SHA-256: 1f8452ee0ccebe2eabab4bdfd788df8eaf90cd91a2cab1bf5bd7585c26ce48ac