Malicious PDF — malware analysis report

Static analysis result for SHA-256 8167bf22727b42fc…

MALICIOUS

PDF

174.3 KB Created: 2021-07-16 09:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9f07ef74db3b6e39154c73927ea818e SHA-1: 50f075764608ace9b7ef82e59ada7147d4d72db3 SHA-256: 8167bf22727b42fc6270ef3d17c9678a1a42e655ba6d9272c23f47e0bf1eb2bd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO spam or to redirect users to phishing or malware distribution sites. No scripts were extracted, but the structure and URL patterns are indicative of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

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://primax.fr/wp-content/plugins/super-forms/uploads/php/files/g8593osh2bk3kut5ontfambui3/3300490020.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/db4e110e37a2bdaa5e326e999c1a77c8/5401252452.pdf
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1ef32f653ebb442a35bbb0c0430a82ec/2047950478.pdf
    • http://artkulinaria.pl/sites/default/files/file/notujun.pdf
    • http://aftckwt.com/uploads/file/10350012164.pdf
    • http://dambi.pl/userfiles/file/jupumobedilafobek.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e5cc636a7d5---mekasurijasep.pdf
    • https://easy2ticket.com/upload/files/83138579006.pdf
    • http://tasarimak.net/ckfinder/userfiles/files/43762537893.pdf
    • http://ccspevents.com/clients/24998/File/ravafifetadetiwenurik.pdf
    • https://mzr-avocats.com/buddha/ckfinder/userfiles/files/11249116762.pdf
    • http://faxik.online/ckfinder/userfiles/files/47444473320.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/ae0ae652b3cffff92ee70f9e5e78b591/31016462191.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160baa840661cc---wubikefomepojuva.pdf
    • https://ready4use.ru/uploads/files/94792923921.pdf
    • http://fitnessklub-impuls.pl/uploads/assets/file/kozadekudujosixutefo.pdf
    • http://artecgroupservices.com/imagenes/file/86136537216.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607112a69ab2b---28100979457.pdf
    • http://olversonfamilyreunion.org/clients/5/51/51a48c89da211807e19ed56f8a1a1822/File/68279708335.pdf
    • http://sklepjola.pl/userfiles/file/84236158067.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a41b8bf1230---labibiziwik.pdf
    • http://www.heksan.com.pl/file/96290684564.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=some+interesting+information
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00022c7f.bin
4d19864aed9ebac699beb24c256c6bdb7c0739e83ec5ba8205cd612503ec8d2d
pdf-font-stream PDF embedded font (sfnt) at offset 0x22C7F 10588 bytes
font_01_sfnt_off0002449d.bin
1089d3e8b162b3217c2715b3e2fbaeccb1da30ecd67147ac69347d925b289a76
pdf-font-stream PDF embedded font (sfnt) at offset 0x2449D 21524 bytes
font_02_sfnt_off00027d80.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x27D80 16792 bytes
font_03_sfnt_off00029591.bin
42f062fc3b196772dad797414c8411d6d46563cdb5fed1c1f34e41b72797b8f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x29591 16164 bytes