Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8779f2cdc0153ab…

MALICIOUS

PDF

86.0 KB Created: 2021-09-01 22:20:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ac51bd0c7838bc3d6beff463e17ec5d2 SHA-1: ca4a05775634ede2aa87d8cc478323d1cdbf2ada SHA-256: f8779f2cdc0153ab7d35c5c922384132a5202ffcea08dfba445f9ad2fd7f0a88
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to various websites, some of which are hosted on compromised CMS platforms. The presence of 'utm_term' parameters in some URLs suggests a phishing or SEO manipulation tactic. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://infrive.ru/uplcv?utm_term=why+do+pine+trees+stay+green+all+year PDF link annotation
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/p5h22f7li2b53cjotmv6bk9hnh/82294113413.pdfIn PDF document text
    • http://sparkpro.lv/content/file/96117479747.pdfIn PDF document text
    • https://najlepsze-w-polsce.pl/uploads/46131467782.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/28978135089.pdfIn PDF document text
    • http://tsg-edinstvo.ru/userfiles/file/vosulevewijivot.pdfIn PDF document text
    • https://peterdegendt.be/file/34329159233.pdfIn PDF document text
    • http://thepnguyentran.com/media/ftp/file/komisolotedodefo.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/e2404t3h0kgpkbip29vggk8qj5/81046099413.pdfIn PDF document text
    • http://ekotop.eu/userfiles/file/70211248473.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/78837408921.pdfIn PDF document text
    • https://toolsatool.com/userfiles/files/vawifoluxazonololar.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927ccdd9971---tawivoto.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/vijonipiwababekipixe.pdfIn PDF document text
    • http://xn--d1achljw0b.xn--p1ai/content/upload/nifusutajo.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/resatitisixatuge.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/vuvovudujokulafoli.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/zojajanuverusepijokelopo.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/77424333480.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/88974004019.pdfIn PDF document text
    • http://banglenhospital.com/UserFiles/File/vanupovikipirudan.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/aa15addef6edcce578b3a673055d1ead/97455127502.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/6849181732.pdfIn PDF document text
    • https://robertbah.si/files/file/suvobovomujadedujetatig.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_off0000ec1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10431 10776 bytes
SHA-256: daa3f2b7ff3e83d9e3d60e9caf9cea3ca6ffe14282fc7573ac8d9d4c1ef54e54
font_02_sfnt_off00011cbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CBE 17216 bytes
SHA-256: 24f1ca0ab5387af874d62bfbfb5645ccaa9068f783f0de793fba98ac34ab0852