Malicious PDF — malware analysis report

Static analysis result for SHA-256 91cb61e0b6e96d64…

MALICIOUS

PDF

79.2 KB Created: 2021-09-13 13:06:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e51bd43b00552a4a23a04819fabbe1b9 SHA-1: b2290cfc0977f2a9287de9f76847b84004a91fdb SHA-256: 91cb61e0b6e96d6476ec74cf960ef71ef7422c6c2d3b7d1da623b9b827a4e056
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links pointing to external resources, many of which are hosted on compromised WordPress sites or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of numerous links suggests an attempt to obscure the final malicious destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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 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.
  • 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://modernplating.com/userfiles/file/87985042383.pdf
    • http://myphamlulanjina.com/upload/files/69055955386.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec1dfdc920---podoxemabovifekozasosaruw.pdf
    • http://www.cddfct.com/up_files/file/malibilosixemubedugavig.pdf
    • http://qlionshousing.ca/userfiles/file/84360515573.pdf
    • https://dcicz.org/userfiles/file/fosojudezemaledoguna.pdf
    • http://sibmaxi.ru/userfiles/file/bukofaxumofozewoz.pdf
    • http://kasand.com/userfiles/disawujuza.pdf
    • http://asijskepotraviny.cz/files/file/26431747183.pdf
    • http://aokunoil.com/ckfinder/userfiles/files/85136740690.pdf
    • http://adveotec.com/img/file/54616524799.pdf
    • http://ned.ru/uploads/files/50389512065.pdf
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/80253014687.pdf
    • https://mmgrowersg.com/ckfinder/userfiles/files/vagujixomopuvix.pdf
    • https://cissud.eu/uploads/ck_editor/files/vitibizunivu.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133dedf19744---wevuwexawidumujapexow.pdf
    • http://nuuts.mn/uploads/assets/tefudujesumakiser.pdf
    • http://tetobox-budapest.hu/uploads/files/netajodipeku.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161346d3f47c27---90867173501.pdf
    • http://langeline.com/ckeditor/upload/files/vezudibipazena.pdf
    • http://rinsacars.com/files/others/pagasivaxizefumozopavipu.pdf
    • http://resheto.ru/users_images/fck/file/difolonajuj.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16136498a75377---ximekiduvused.pdf
    • https://alyosserspneed.com/userfiles/files/fijok.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=call+volume+too+low+android
    • 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_off0000d161.bin
110abe260ae3f3538a95575682f4bf9690eef060d2765174df284b44b6b8f85a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD161 17560 bytes
font_01_sfnt_off0000ff1c.bin
e500a25058f2c8fb6228b74572fd21d4503ee3f85f23efc17adca8f55704b1d2
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1C 10524 bytes
font_02_sfnt_off0001171c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1171C 16792 bytes