Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd284aaeccd20e5d…

MALICIOUS

PDF

68.2 KB Created: 2021-09-30 19:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 74253be41d72c628626f9efa03683404 SHA-1: 5da0b63c5dd47b32bec25b96d9b12de009dfbd65 SHA-256: fd284aaeccd20e5d2141d8baae1ebfb29bea13ce36fe6d4d4e15c162d0d40cf0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm. The embedded URLs point to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or manipulate search engine results. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis strongly indicate a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://shreeaksharinternational.com/webroot/img/userfiles/files/59750954699.pdf In PDF document text
    • http://bebaldebaran.eu/userfiles/files/66448138870.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/37506968454.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/55150132453.pdfIn PDF document text
    • http://bjxbw.cn/userfiles/file/fixumazefapusetugitunig.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/36882169535.pdfIn PDF document text
    • http://gniortho.com/files/Upload/file/71141368607.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/tiduxoreluzalikotibak.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c63f49d1e9---69888044333.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614b6e6e00b35---wotezexoluzarolizimod.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/tirorizonubabepozalikiba.pdfIn PDF document text
    • https://goodmix-psc.com/userfiles/files/vusoxakolugajusewevuf.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16137d1a92f2aa---80765283168.pdfIn PDF document text
    • http://china-guolin.com/filespath/files/20210920160340.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/tibewudaxivod.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/50777611901.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/2062753886.pdfIn PDF document text
    • https://miraclechuppahs.com/userfiles/file/61331289104.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/fivinuvitu.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/donomunalaz.pdfIn PDF document text
    • http://qlinairnv.be/userfiles/file/31897818967.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=phrasal+verbs+with+make+and+doPDF link annotation
    • 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_off0000abcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xABCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c3e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3E1 14996 bytes
SHA-256: 05311feb8d97e1973045b8662c0d3cbf4415eb9b7febd03d6d652e540c5f3876
font_02_sfnt_off0000ea1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA1E 10896 bytes
SHA-256: f4fd2bc8334218a2c20e0dd75db805ace6bcd9305bd851a28aa97f42367bc6ee