Malicious PDF — malware analysis report

Static analysis result for SHA-256 535455673e9c9582…

MALICIOUS

PDF

87.5 KB Created: 2021-06-26 00:17:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 34323bf7a2ea184e08c9e811b67c1f1e SHA-1: 9b72202ab0754a60560f7c009d747172a9dda7a0 SHA-256: 535455673e9c9582c088443840d894b723aa1cd8b91dcbf1f5d5429c598b9eda
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to external domains, many of which are associated with compromised CMS uploads or appear to be part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://ipsgroupjjn.org/userfiles/file/61310364230.pdf
    • https://citronixdeflection.com/nbloom/fckuploads/file/jogegeguke.pdf
    • http://uro-medical.pl/zdjecia/fotki/file/zenuxikekogaran.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/8916c839dd30bbbc9e598cbb8635f1f2/91567709777.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c79ef361a5---61409220617.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d046380f7c---14507212398.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16090e3d5bad36---tixinavawigejujabo.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1e4ea73e91---40346515118.pdf
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/b5141a36074b76f9198b1ac839ebb79c/pitevemaginerewutitupo.pdf
    • https://dimensioninteractive.com/WYSIWYGImage/file/41053923534.pdf
    • http://fashioneducation.ru/userfiles/file/gamitipisuzuna.pdf
    • http://goodtraefarm.com/ckupload/files/vesinowefuwijer.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2e6fb5c95f---14018131987.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160bfacfb29aa0---49967892765.pdf
    • https://299-45.com/CKEdit/upload/files/15843122923.pdf
    • http://aweibel.com/Photo/file/26758733572.pdf
    • http://zahradysnapady.cz/soubory/files/88425351028.pdf
    • http://extracam.es/app/webroot/arxius/file/89353775444.pdf
    • https://mindspacepsytherapy.com/upload/ckfinder_temp/files/20210528232809.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f9bbf26cd---nudupofifitedexineke.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/b0696e7a1882fd82a60037c475230ce9/66564866587.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f870c37e8---lalod.pdf
    • http://xn--dlek-5qa.com/admin/UserFiles/file/43230677650.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16084d50bc584e---xemetamuk.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/dss49h29rtgef7otrllvuekbv4/nasifobofiweninekugo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+start+making+rap+beats
    • 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_off0000f16d.bin
6dd24c4b7ffcba12b0caefd8401b2d5851353b499ff35eda988eb4d0761bf179
pdf-font-stream PDF embedded font (sfnt) at offset 0xF16D 17332 bytes
font_01_sfnt_off00011e58.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E58 16792 bytes
font_02_sfnt_off0001366f.bin
c463e8e55c924256aafad6574936052c0a8ca8106f973112f5d059c72aae1c59
pdf-font-stream PDF embedded font (sfnt) at offset 0x1366F 10856 bytes