Malicious PDF — malware analysis report

Static analysis result for SHA-256 993681c612faa060…

MALICIOUS

PDF

89.3 KB Created: 2021-09-15 22:42:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b39bd5ddbc27986e5c158f4b78d1ec7d SHA-1: b6b4e0e8233f5cdb896f80ff4ff2675cb6683135 SHA-256: 993681c612faa060309f24c09dd36d816d5442e81ffbb5e25d2da88183508c92
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links to external URLs, many of which are hosted on compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://only-svet.ru/upload/files/mojudi.pdf
    • http://staropolski.net/Upload/file/80550649520.pdf
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/diwisafalejaxixoxulatupag.pdf
    • https://www.jdconstinc.com/ckfinder/userfiles/files/81120722032.pdf
    • http://blow-w124.com/js/upload/files/10343618162.pdf
    • http://ohmamakitchen.com/uploads/files/jopiraso.pdf
    • http://nuovojob.com/userfiles/files/busogakiwenem.pdf
    • https://www.khaosanpools.org/ckfinder/userfiles/files/zuvet.pdf
    • http://makeyourpartnermelt.com/userfiles/file/fumojezevevokevoj.pdf
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/32512118243.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613edf91299c1---893636163.pdf
    • http://gesht.ru/admin/ckfinder/userfiles/files/17402458325.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pb97ok71q0k07kp55ki0sv5t75/betusamejozemoxojukosabuv.pdf
    • http://kxqcgs.net/filespath/files/20210905160516.pdf
    • http://morard-mcf.fr/data/Files/pujejasusoro.pdf
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/fipakawidugukilape.pdf
    • http://patrick-vallot.com/upload/files/niterotofoxapuwaripi.pdf
    • http://abwcrainhwy.com/uploads/files/54571742696.pdf
    • https://fereshtegan.net/basefile/fereshtegannet/files/dufok.pdf
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/373227593099ed9f535e9d8623ec943d/wimomonawavajixi.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136475901413---92780179503.pdf
    • https://sheenabusesandcoaches.com/userfiles/file/xewajatoxarafififotow.pdf
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/lisuronuz.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+transfer+all+photos+from+android+to+pc
    • 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_off0000f957.bin
b8352fd64e7c92e79b9cc2fe6666e148e273cf890c32af8d790d1fb913690d44
pdf-font-stream PDF embedded font (sfnt) at offset 0xF957 10960 bytes
font_01_sfnt_off0001128c.bin
922fb80f44eee53fd6c9574307aca08e34eb28fdd7bac502f87d9b707526805d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1128C 17408 bytes
font_02_sfnt_off00013fb3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FB3 16792 bytes