Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7b508e94c6c9836…

MALICIOUS

PDF

85.1 KB Created: 2021-10-05 13:19:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3b3cd650b40277042d78bec719a5bef3 SHA-1: 698618b08f44f1f8f18bf9187778b149b1215322 SHA-256: e7b508e94c6c983691c947aeb30dab1522d62eaece4e7c1a29a7a2826c4813cd
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS uploads or disposable domains, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://irlanc.ru/uplcv?utm_term=melon+fruit+in+english
    • http://madurastones.com/userfiles/file/12564896282.pdf
    • https://ngusacdon.com/upload/files/namigosu.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ea88e8a5f7992fa5470e991078187075/susijezorifobajukilog.pdf
    • http://agro-vostok.ru/userfiles/file/mujuxixivonizebiza.pdf
    • https://ezsprinting.com/userfiles/file/33042633080.pdf
    • https://decoveinvestment.com/userfiles/file/99334497823.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161429c4143253---19294649240.pdf
    • http://cnwt.mgo.cool/upfile/files/2021/09/24/pesinefibesubunaleradopi.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161583af313d72---lavoropitesiz.pdf
    • http://porpora.group/imagenes/imagenes_contenidos///4738323757.pdf
    • http://msiutilities.biz/documents/15702040298.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d36de78413---resejaromuzewe.pdf
    • https://promptcorporate.com/ckeditor/ckfinder/userfiles/files/73081791718.pdf
    • https://www.cosanuesa.com/componentes/editor/ckfinder/userfiles/files/83745115753.pdf
    • http://commandhousecreations.com/uploads/files/noletudomapobiviki.pdf
    • http://dreiseengrundschule.de/files/zadovug.pdf
    • https://aromamarketing.md/img/files/rekisof.pdf
    • https://siliconautomation.com/userfiles/file/87085818410.pdf
    • https://girisimhaber.com/uploads/file/68210433919.pdf
    • https://encoyun.com/calisma2/files/uploads/tojaxuxusetidigasize.pdf
    • https://flyags.com/editorResources/file///bukedorifa.pdf
    • http://kramor.bg/userfiles/file/44890945045.pdf
    • https://ibericadearmerias.com/file/65444209368.pdf
    • https://ptogel2.com/contents/files/debibiluzukalisir.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_off0000de17.bin
34354ee0e3b696271daf5daccb8928e48ffb311f4bbedee63a3c6d454e159e8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE17 10424 bytes
font_01_sfnt_off0000f5a8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A8 16792 bytes
font_02_sfnt_off00010dba.bin
850cecf8b11311367017a5efe6224170067acce45747d8c0b6b214d135fae07f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DBA 22136 bytes