Malicious PDF — malware analysis report

Static analysis result for SHA-256 831bdb101d459cba…

MALICIOUS

PDF

82.3 KB Created: 2021-07-05 05:35:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea4f4cde5f179b876c9e400edf1b17b7 SHA-1: 15c6bba04557405eaf82429b631840588d30754b SHA-256: 831bdb101d459cba9d0f2c0d5a4f56637613524c0c62d05363cc0d53b3d372ab
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://ergo-logo-bamberg.de/userfiles/file/61505057874.pdf
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743be2b8751---nabuloz.pdf
    • http://northphoenixmustangs66.com/clients/4/4b/4b49b54eec06ebba3741256e9f3e6f2b/File/jagurowarizemevafo.pdf
    • http://global-insurance-broker.de/downloads/besaxaxa.pdf
    • http://mottaing.eu/userfiles/files/revijumukugimimexuz.pdf
    • http://nuraski.pl/wsg/userfiles/lokimogozulojofipewipi.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160982f3021e47---piwireso.pdf
    • https://goodluckfishing.com/ckfinder/userfiles/files/52608139611.pdf
    • http://shinies.ru/img/lib/file/tozuvot.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/12e6509fc995e6ada154b8eee9df8779/98663774791.pdf
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/d5a95999257153bc350bcb0f2949bcfb/timikulenu.pdf
    • http://dyglas.com/userData/board/file/senituj.pdf
    • https://pacantioquia.org/aym_image/files/44636813431.pdf
    • https://menu2uplus.com/images/file/kemisiradafixexi.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e41e01bc5---pumuzedofizasuvefu.pdf
    • http://timapools.com/uploads/files/sivixazu.pdf
    • http://promador.pl/userfiles/file/jefaromefureruvedux.pdf
    • http://alkanboya.com/files/file///73245961785.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160824cddcce12---1292136277.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/gthaqjj8pfc15r58se3qj3c0du/52586654008.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd41c60b648---3237867748.pdf
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/79759603402.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160dca76c8eca8---81178602996.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=balance+the+following+chemical+equation+class+10
    • 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_off0000dd4e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4E 16792 bytes
font_01_sfnt_off0000f565.bin
885ed0915082a8b9a0a3ab67408db73e93ec2f9eceb35ecd5d91da61868ccb56
pdf-font-stream PDF embedded font (sfnt) at offset 0xF565 11240 bytes
font_02_sfnt_off00010f61.bin
56c05aa6fdd93854e988c5d5b44d101643ac72c7cad00b75b5b6c0077f0a6e29
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F61 17136 bytes