Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1c1b47c82406079…

MALICIOUS

PDF

81.4 KB Created: 2021-09-18 09:51:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3f3337d7399f52e304e6c4ba9602b23b SHA-1: 5d341beefd13c4c1dadb5e900aa45489746bf5b3 SHA-256: d1c1b47c82406079aba7df14180297176564103f9bf9c3fabc83f00894b43fe5
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads or appear to be part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • 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://allytemp.ru/uplcv?utm_term=words+beginning+with+sa
    • http://www.naturhalles.fr/fckeditor/userfiles/file/94155355279.pdf
    • https://eminentland.com/admin/userfiles/files/ravoj.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/906453071de3da5eea6a57271670daeb/nusiguj.pdf
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/98999876052.pdf
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/kimuduwikipazonaro.pdf
    • http://phuketdriveschool.com/userfiles/file/66058600665.pdf
    • https://nakipoglugroup.com/upload/ckfinder/files/36962276107.pdf
    • http://intrinhgia.com/admin/webroot/upload/image/files/77935446928.pdf
    • http://osstemcardiotec.com/files/fckeditor/file/131715193861340b6d0e1ff.pdf
    • http://bygreenpure.com/userfiles/file/kapoxesolenotenezekulidam.pdf
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/15152181126.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142acdf56de0---88862005161.pdf
    • http://kancelaria-perfect.pl/app/webroot/media/files/fomevebixujap.pdf
    • http://ncfc.com.tr/ckfinder/userfiles/files/53714463379.pdf
    • https://ashasuchikala.com/ckfinder/userfiles/files/warasizanivukerezerugowo.pdf
    • http://luxcottage.ru/stroykamen/userfiles/files/67208855035.pdf
    • http://www.findvoters.com/userfiles/file/25574540209.pdf
    • http://capesociety.ca/uploads/files/15044771599.pdf
    • https://xeroxexpres.cz/userfiles/file/83646513697.pdf
    • https://abyway.lv/images/ck_images/files/62122759157.pdf
    • https://khangle.vn/uploads/images/files/44471774519.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eac7cb0214---tezusokuj.pdf
    • http://mlsconsulting.net/cms/files/File/podegupiburutupawom.pdf
    • http://slovoveri.org/userfiles/47146521751.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_off0000d85c.bin
a908ff969a7bb77cbd67007d9f65f4dbf271edf6b83db66d632f2540c1bf81de
pdf-font-stream PDF embedded font (sfnt) at offset 0xD85C 10700 bytes
font_01_sfnt_off0000f0b6.bin
14fed92dc292985b89dffb6b03a316af13ffb3bdf27b81a8954442d1e48f2aae
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B6 18268 bytes
font_02_sfnt_off00012025.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12025 16792 bytes