Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bbb35e784f9b556…

MALICIOUS

PDF

87.2 KB Created: 2021-07-15 16:26:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 58f007b702fd82d5a33bfbbb85bdec9f SHA-1: d0f0cd75c0af5730583e358f9948796d5ce1e65d SHA-256: 4bbb35e784f9b556a5f3794d43ea1f5cb2b5347ed3f82e30fb53f676f69af02a
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of external URIs and compromised CMS upload links are key indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://philabc.ru/uplcv?utm_term=compensate+someone+for+something
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607345f29d4ea---49220461640.pdf
    • https://anmimar.com/royal/userfiles/file/74485536758.pdf
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/d9hps08213dfh9bph953l707o3/tuxotujetasulozanususepub.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a58fef15c---48539798273.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160822f84879ce---dutesadofewigo.pdf
    • https://atl-50.com/files/file/65022939157.pdf
    • http://chronicles.ae/userfiles/files/15163346780.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095e81ed3242---91788574960.pdf
    • https://alice-immo.com/userfiles/file/sujivuxud.pdf
    • http://dharmapremipariwar.org/userfiles/file/bixufuf.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2309a73a3---fuxibuwejunaper.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/gbc26evq5ilc897i0s93a613p5/73858420546.pdf
    • http://zaun-produzent.de/userfiles/file/mumaxowupisoso.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b78066df837---bolatexuwetosat.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/5d92f005e5dbb41c2cf39b33e2f0787f/67959323831.pdf
    • http://cichanski.com/Upload/file/susomapadurukakam.pdf
    • https://unibel.pl/pliki/upload/file/16546367999.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608752d93c617---jorukatu.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/5bc0b38163a479abe348dad19697febe/megufa.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/54rc2gvkc7jf67fhuj91u1358t/9082704324.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2fbe74db18---kutigizafapol.pdf
    • https://eastmanllc.net/ckfinder/userfiles/files/25826006935.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079dc67267a3---voboxepasivix.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4d5386695---gijalinufebus.pdf
    • https://thinkhigh-tech.com/d/files/tanewefuwerupago.pdf
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/04gs89uvdjbgmutobhevnc9530/16698701908.pdf
    • 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_off0000efb4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB4 16792 bytes
font_01_sfnt_off000107cb.bin
bc67fc90c8c5feab12fb416ae6a76dd4b249d2110a011eba15ef43dd705e31f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x107CB 10792 bytes
font_02_sfnt_off0001207b.bin
f565af9c8622526a60452008abb364b9357a02ee6853b78bdfffb2c2fb463beb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1207B 17252 bytes