Malicious PDF — malware analysis report

Static analysis result for SHA-256 55de9c2cbcf60393…

MALICIOUS

PDF

90.4 KB Created: 2021-08-01 10:41:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7ba739aca2a273c4e42264627378bd53 SHA-1: 01db3274d549e41f6a79d7344390fb740dd65e5f SHA-256: 55de9c2cbcf60393300c7c4847997c8ebca908b227e1155c15e8a97e2315eba0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely exploits vulnerabilities or contains malicious links. The heuristics reveal it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous unknown URLs suggests an attempt to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://dlevitin.ru/fck_editor_files/files/15587732319.pdf
    • http://arslanemlak.come/file/luterixapisaj.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/32vd6ddshftdsimk1873esjec6/67587080490.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc911c168f---fibomusurimabipe.pdf
    • http://nenkin-t.com/upload_img/ck/files/penepone.pdf
    • http://www.lnk-creation.fr/upload/file/burozadorumo.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607a459114c59---tusemefavage.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/bbfb74401f9e9902503af0b9932b5657/ramutix.pdf
    • http://www.serenissimaservizi.com//files/pujubezilavitosepatax.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/dadjqrjbsm9hggi305tb1blsp0/kifawuwijumu.pdf
    • https://mudraconsultancy.com/uploads/files/bavajajigizudusu.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/ed5d959f17be78aa6ea3446e0a9e6ac4/10445404061.pdf
    • http://heatexchangersolution.com/upload_fck/file/2021-7-30/20210730194611566242.pdf
    • http://dokumsuzgec.com/userfiles/files/79242752490.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ddd8be00649---bojobumuvevurajifusol.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607903eb5975e---mamoxefutijenojebobeb.pdf
    • http://alphasigmaoverseas.com/userfiles/file/zusetozoregun.pdf
    • https://baoholaodong24.com/userfiles/file/gudasabunagosodu.pdf
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/e21cb4ea65c7c7ab13d85621907be5f9/62407055927.pdf
    • http://arebiatours.com/uploads/files/52654002190.pdf
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16099b02dc252f---zoxezas.pdf
    • http://thementalhealthadvocates.org/files/userfiles/file/63685722041.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0eaf870cfb---13926203165.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=weird+but+true+facts+about+love
    • 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_off0000fb64.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB64 16792 bytes
font_01_sfnt_off00011376.bin
d64df446aba16e29e13d16f83781a8887436875acea8a4745a379d98a0ef91b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x11376 17660 bytes
font_02_sfnt_off000141cb.bin
de55a2a3f09d52939c5cdd3ae923d3b95d3a0197283e75265cca202c0f16f64b
pdf-font-stream PDF embedded font (sfnt) at offset 0x141CB 10664 bytes