Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a3a78ac16e3a0cd…

MALICIOUS

PDF

87.4 KB Created: 2021-09-08 04:25:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0c0c3d245fdac69384735940cb0a872a SHA-1: edd0e94c4020e235d35e558a6c29e6ef8122862b SHA-256: 2a3a78ac16e3a0cd4d01e28ac46a3f234d474bcb5580c0ba028b30c3bfb9cbe3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, with several pointing to compromised CMS upload directories, indicating a potential phishing or SEO poisoning attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan. The document body is heavily obfuscated and appears to be generated content rather than user-readable text.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://chinasoftcore.com/userfiles/file///2432468473.pdf In PDF document text
    • http://afghansolar.com/userfiles/file/43754362418.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/wogapomum.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/77013940731.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/89004215104.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/xubigemusug.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607189a24e9d6---6507566547.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jutak.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/37110060087.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/eitv5fjf9sn86v9oop2igc1n3m/ximesubijesomotiliruse.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/4f5b40dccf99d82ab6cc2432397ab1ac/pumoxabebefiboposi.pdfIn PDF document text
    • http://salwex.hu/file/81746137174.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b78c1ee21ee---gasijelomexeku.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1544112ef7---83272159060.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/95677671609.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/94580296078.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/17975933644.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/jerukiwivavibus.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/xazevovefuzu.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b3d48ac550a---niradavawasoxogonupenovem.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/16114f883bf78a---vofarula.pdfIn PDF document text
    • http://terminsk.by/pics/files/silojasukujimarokusudonij.pdfIn PDF document text
    • http://nessium.net/userfiles/file/pamivukor.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/jigupelibiveloxuruzuler.pdfIn PDF document text
    • http://turnyras.lt/Files/file/79570869863.pdfIn PDF document text
    • http://viettelhaiphong.me/data/dulieu/files/jagodagijiguz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=harmonica+beginners+pdfPDF link annotation
    • 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_off0000ee15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE15 10948 bytes
SHA-256: 393cc29de0fa763ba4240b50a592bc27fc133992edb0e69b7040eb3c4e6f58cc
font_01_sfnt_off000106f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F3 18616 bytes
SHA-256: 9bbb09c138a8a2ae1b2d4448d6617f0bb38842e61f36b550907f98a555d69ccd
font_02_sfnt_off000137d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1