Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdc57f6d9b4f582b…

MALICIOUS

PDF

88.2 KB Created: 2021-07-17 06:52:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e93df356a9f300a30047ba1a975411dd SHA-1: 5726ff737946c29ffc85f1eede04bd4869cb2aec SHA-256: bdc57f6d9b4f582b9c30eeb0c28e82f2f47ca616c7b6f6da10f6a4a0883e9dd6
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised CMS upload directories, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of numerous external URIs and the link farm structure are key indicators of this attack pattern.

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://farmaciafoglia.eu/userfiles/files/joxesiletipirefesajata.pdf
    • http://gachtrangtritranvinhtin.com/gachtrangtritranvinhtin/Images_upload/files/18403866522.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/ctcjhq9oab8milh9ok01p5rbgv/golipebaxamoforujexorozaj.pdf
    • https://mamo-tato.ro/userfiles/file/17360713363.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/ecb22d723d9608134f404e104a394133/73020609030.pdf
    • http://eltonltd.ru/sites/default/files/uploads/waxuvugudososu.pdf
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/jetasutodofox.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777a289ed09---balare.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609adfd25654a---pexibazi.pdf
    • http://pogservice.ru/userfiles/file/73925419756.pdf
    • http://cngwalk.com/fckeditor/userfiles/image/774357714.pdf
    • http://vintageguitar.ru/ckfinder/userfiles/files/lujumesepuzijupelo.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a23ced350ee---dadejisefebabuxukilaf.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/49a1a64bc651f9bd4913af7a42ba7ff7/25653697338.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d6959fda5---66430346482.pdf
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099df240cdd8---xowubisodarivoxet.pdf
    • http://jullien38.com/ressource/site-image/files/98892390881.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3e8b01e68---nilumagenevefejadimi.pdf
    • http://chhsmahs.com/clients/8/83/83f479e57a8bbaec88b4a04d821ef24e/File/59128654355.pdf
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/lvk7iabj0a9i2he7q9djco2b1d/bogurutezusudukal.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab80772c6e---52666179384.pdf
    • http://krzeptowski.pl/file/kuviwadikunovolefibaxer.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4c7fef11b---37307249765.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/33e867e91edd5f1d5b7f40ffeb3db290/dimosege.pdf
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/be8e8f10f26d8964a72d746cc5507e65/winabosirenigexi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=repurposing+coffee+cans
    • 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_off0000f435.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF435 16792 bytes
font_01_sfnt_off00010c47.bin
4b9987ada48ee03ea212d5dcb257caf20932ecc2aa56e17b4748fc40447b7289
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C47 17252 bytes
font_02_sfnt_off00013999.bin
4b383261eec7cd9217cc3832405fc4ea74b12aa07c52a7182889e1ad33026042
pdf-font-stream PDF embedded font (sfnt) at offset 0x13999 10656 bytes