Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d61a977d8cd7602…

MALICIOUS

PDF

82.6 KB Created: 2021-09-18 23:12:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2ea7dcbaca5ef16ff7f130dfb21f97bd SHA-1: af79ad4f6ce253a87d0bf4c9ea146b85eb9a2193 SHA-256: 8d61a977d8cd7602eb98017bec9f22b5de8759bbd8f58f51386ced5c8209b8d5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or downloader lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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 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://silverlabpupsforsale.com/userfiles/files/zabazufokeb.pdf In PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/tavegazerug.pdfIn PDF document text
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/92299136888.pdfIn PDF document text
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021090922203480554.pdfIn PDF document text
    • http://c-amc.com/upload/files/bakopofumu.pdfIn PDF document text
    • https://minlinart.com/archive/upload/files/85383591723.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/mowemirofakulorevad.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/ccf2e581abd633f7c1394357a83c11e1/lovasapon.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/72351252805.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/kamobawaliv.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/vupikelazolejefuzopit.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f27e3a9512---81248343051.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/86973268724.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/zapizininot.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/71256770189.pdfIn PDF document text
    • http://vtaky.sk/media/file/korata.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/c8a72c4098dd19f0f1de9f140116cb63/19758063802.pdfIn PDF document text
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/52838494735.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210903_131720.pdfIn PDF document text
    • http://skene.es/userfiles/file/gudolotisowibobarezixuwas.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/24502211305.pdfIn PDF document text
    • http://gleb777.com/fck_upload/file/67403515504.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/244a86903fd8289d00f80c4bce7a9bf3/41528372942.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/zuwodunawilukagi.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/sojowakaturumogotep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=download+film+wrath+of+man+2021PDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF6 10700 bytes
SHA-256: 7a1743757984fae38e1a2c61dd96f5b925a50fa676eddd8d76372e8611d811f9
font_01_sfnt_off0000f65c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65C 17972 bytes
SHA-256: 1426ed05ad26d02217e9d756a54ccfd345c7f3d5ad71e26904477a51960a3ab2
font_02_sfnt_off000124b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1