Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca55f3165098f377…

MALICIOUS

PDF

77.7 KB Created: 2021-09-17 22:55:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 658478db4d2989e3076da3ef092655dc SHA-1: 727dc6cc21190f52c8a663a63dda3e73b4995fd1 SHA-256: ca55f3165098f3777c5e4cc3e37f67c59eaa71af4e528e8dd1e7c8c8c8faaa6d
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external websites, some hosted on compromised WordPress installations or disposable domains. The embedded URLs suggest a phishing or malware distribution campaign, aiming to trick users into visiting potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • 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 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://crysiq.ru/uplcv?utm_term=no+ad+mx+player PDF link annotation
    • http://tjsyjdq.com/v15/Upload/file/20219522504840.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210912103607.pdfIn PDF document text
    • https://gilbertems.com/videos/file/2021731257.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/34421464978.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/datepolume.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202109140627023161.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c3d52c778---58909103858.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/rimirulepozum.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/xejotabafeduzu.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/wavipojudaxifutox.pdfIn PDF document text
    • https://lorus.rs/files/70447568423.pdfIn PDF document text
    • http://szilasfood.hu/pic_upload/files/25303285937.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/17165108969.pdfIn PDF document text
    • http://esistore.de/userfiles/file/puvoxozegowefesal.pdfIn PDF document text
    • http://sedaciesupravy.sk/media/file/xukefe.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210912_ED35336B6C3A747D.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/064ded89f35b8fa3cc4f80e6f3418263/dojatomewexefa.pdfIn PDF document text
    • http://a-aqua.fr/ressource/site-image/files/xulek.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/96174494073.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613996af84e7e---gotasazolafek.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131f85400223---tupowesevezujominiwoxifig.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/nelirofap.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/44538544729.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cbb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB8 10284 bytes
SHA-256: 19fe8e27557074b2a0aa9797d76f6b87dd75a9b4e4ee487f7411d468c8fdf2c8
font_01_sfnt_off0000e2e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000faf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF2 17588 bytes
SHA-256: 264c2b69b6e3277a0a679cc6158b04f2365054361741384d404561855c8d6cd0