Malicious PDF — malware analysis report

Static analysis result for SHA-256 33713594770ab318…

MALICIOUS

PDF

70.3 KB Created: 2021-09-09 16:51:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: eb739bc30bccb8c8753e6ccf7e9581b3 SHA-1: eef508f24c44cee2fa5bafca5c557a866e4ed932 SHA-256: 33713594770ab318405b6d7f8751c0f0e57aa49817e2300b81a1ff076b995ccc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://terracell.pt/images/file/30047611197.pdf In PDF document text
    • https://turdv.ru/SITE/files/editor/file/73286688963.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/woduromalujiwimujifupo.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/42385181494.pdfIn PDF document text
    • https://bomando.bomsolar.com/uploadfiles/files/69759478642.pdfIn PDF document text
    • https://cukimentescukraszda.hu/files/files/wixotesar.pdfIn PDF document text
    • http://benevolo.it/userfiles/files/71449624105.pdfIn PDF document text
    • https://getadoc.in/ckfinder/userfiles/files/mofazavigapuve.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161346f048c286---fipiwuxisafuwog.pdfIn PDF document text
    • http://jmestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50844637200.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/58009464316.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613096052a024---vivebo.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/8pu77s4m1so2g3jagse4gm94jo/62002060201.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613615f0636f4---21777162970.pdfIn PDF document text
    • http://ariogalospspc.lt/userfiles/file/zefasi.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/xagewevoxedatekisudofuf.pdfIn PDF document text
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/85860428237.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109061248488735.pdfIn PDF document text
    • https://jills.reviewz.eu/app/webroot/files/userfiles/files/42593654162.pdfIn PDF document text
    • http://worldplastsolution.com/ckfinder/userfiles/files/mabajusi.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/dotumegi.pdfIn PDF document text
    • https://kcharp.com/ckfinder/userfiles/files/16864870844.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/folepaxej.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210905143506.pdfIn PDF document text
    • http://classicalgardenfountains.com/uplds/file/tetoveruxajonilolalavi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+download+gta+5+for+android+free+full+versionPDF link annotation
    • http://forum-auto.ru/data/files/69557366084.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_off0000b5b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5B7 14432 bytes
SHA-256: 4658472979f1b01eda229f8b489906fd99aef0b3273aa0dd628fb97ca29b1160
font_01_sfnt_off0000d9ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AB 10904 bytes
SHA-256: 45bde4114f52ee225d547d4a1e22ab2e3c2781a7e3be0123e44b4d361fe2e610
font_02_sfnt_off0000f2e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1