Malicious PDF — malware analysis report

Static analysis result for SHA-256 6421aaa29716fd06…

MALICIOUS

PDF

92.0 KB Created: 2021-06-28 14:03:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 49cf40ccf5ced24eb885af67002b2805 SHA-1: 9b2fdea783fd4591d20bddca073672f9af4248a5 SHA-256: 6421aaa29716fd068a5b996734496371e422b40692e137029af37a254902e855
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download button' heuristic further supports the idea that the document is intended to trick users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ketchas.ru/uplcv?utm_term=free+ntfs+to+fat32+converter PDF link annotation
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b45a3f1f333---poduvizijezizover.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160876d8eadd5f---tanasidutovir.pdfIn PDF document text
    • http://jp-photo.cz/soubory/files/1721527144.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082fba3d5662---86588236025.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085937f165b3---guwiwe.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/67519778936.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/6022f47cabac65a2a32236e3cb4252ff/zenejatawifuvusixiwunakor.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb1b509a65---51923933721.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/tbs7uhdg27qlmv2ja2bbogm03o/bofowixejuz.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/1d551679c6e95e8c1a45f99a21eca4fa/79871731784.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/q54stb2buf8lccpsjj4hmamqd1/luzorifunip.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/1e49d64df30e51189eba76b432fd9f30/21269542270.pdfIn PDF document text
    • http://xn--h1aaebbkfib4a.xn--p1ai/sadm_files/bufibowobubagorawemezo.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/p6frk58uknaq127a6mdaj87t2e/lolal.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/fededilozunagigunigovizu.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/tm0g0iivpu8h77kq0troorhca2/6364868885.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99cc549a82---19886580615.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/7lghtoks1m20qgke3r1beeop82/41240779719.pdfIn PDF document text
    • http://ezibra.pl/upload//file/xugevonasodesipifij.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/ehdcqjl04od5tmvle6u87kncj7/63399156845.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/9a0abb9931984e37d35035baf69d0c6b/mifizumumiwolisuxeju.pdfIn PDF document text
    • https://hfdjet.com/wp-content/plugins/super-forms/uploads/php/files/8b53f9b33d1a68e1d7d3580e5751a428/suxoxusanobativuva.pdfIn PDF document text
    • http://dailycan.com/userfiles/files/debojilosorabuge.pdfIn PDF document text
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3D 10524 bytes
SHA-256: 307656881d3faebd18dce261d0a66bf7889f00014350289376c7c654d10695a4
font_01_sfnt_off0001156f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1156F 1736 bytes
SHA-256: a970dc50f3fc642965faeb3d6f2817be39c8fee70eb220fb851f6e1b0fd382ad
font_02_sfnt_off00011daf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DAF 16992 bytes
SHA-256: a026ec6667ccfc65da85157d3ff60dfae5e6689d51a6d58bbb872c758c2e44bb
font_03_sfnt_off00014a29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1