Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3886bc15996a17c…

MALICIOUS

PDF

75.5 KB Created: 2021-06-30 18:43:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fc111d61b9bbbd86025b14596508cdfd SHA-1: 22a08c863e6c36657bd0ad32c4cb3d33b6ab9f05 SHA-256: c3886bc15996a17c41e9956b4518685555d0b0c22b4bc27fbeb6e13ee54e0fdc
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded URLs and the heuristic findings point towards a spearphishing attachment used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://ailani.org/wp-content/plugins/super-forms/uploads/php/files/9c77eca9b412e90d742aba3417229f3e/pizakumusen.pdf
    • https://avonsteel.com/UserFiles/file/59208469384.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/bd3a264e27b353fd436f847bb4ce3ce6/65827479920.pdf
    • https://secolink.sk/userfiles/file/15715777506.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/8bus97t9us75nmq744195ufuo7/16687942473.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16088746249b55---20832990693.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/06793a215ebd34de3dcc0c548e3da3c3/81613514404.pdf
    • https://mamap.in/ci/userfiles/files/libegesoke.pdf
    • https://bbpartner.cz/userfiles/file/3039641578.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/30cov4q1h7qhd0trnlmf8la595/88717877723.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160bda81dea4ce---64859985420.pdf
    • http://servis-hradec.cz/files/file/tunomazerumulikit.pdf
    • http://centreforeffectivecoaching.com/media/file/legona.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5a2f70ec6---58721950836.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d323461a3ed---68449818010.pdf
    • http://zionhillfirstbaptistchurch.com/clients/73368/File/jenalitidaduzugib.pdf
    • http://bellsazshihtzu.com/clients/878694/File/xijoserafekexezodavuguve.pdf
    • http://hamdard.com/hamdard/app/webroot/img/ckfinder/userfiles/files/70301791631.pdf
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/sutab.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/1uhmkrt9pnochhi7jii18qtvp4/vagawisemurufokuri.pdf
    • http://sdds.be/userfiles/file/13117470507.pdf
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/f1tmon8r5voi4cui6c3atgk0f5/xilapemaledone.pdf
    • https://planet-for-events.de/userfiles/file/pozamupitozovotezodilew.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/s0tf5bcsdpsej0ga3c6au2arhg/pofumonawidivikewototox.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=clonex+labs+inc+uses+a+process+costing+system
    • 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_off0000c4f0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F0 16792 bytes
font_01_sfnt_off0000dd07.bin
3f7fa5c9691306b017d497982277f22db4e55ff393840bd5430c4a6a4b4f8ea4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD07 11204 bytes
font_02_sfnt_off0000f71e.bin
dd86d324cc370f26ebc2a962b17c7387f29d9466840357c8296cec20e8e8fa40
pdf-font-stream PDF embedded font (sfnt) at offset 0xF71E 16044 bytes