Malicious PDF — malware analysis report

Static analysis result for SHA-256 33f55d32d482ad2a…

MALICIOUS

PDF

82.8 KB Created: 2021-09-09 04:07:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8cca1be3bb134b2d4f8c6e696fad7253 SHA-1: 5496555f643360cf187703be5caf17914db6ec87 SHA-256: 33f55d32d482ad2a7aebea3898be9ccda3994810338893bb88bc91d033ee34f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded links pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm used for phishing or malware distribution. The presence of external URI heuristics further supports this, as the document directs users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://nomylo.ru/uplcv?utm_term=plants+vs+zombies+windows+7
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/ba47d4db39c72aba79781aeecf40cd1d/89362809844.pdf
    • https://membermimpi.com/contents/files/48059662771.pdf
    • http://fst-uinsu.net/userfiles/files/15805175007.pdf
    • https://copacndg.com/images/uploads/files/85600424124.pdf
    • https://bruceleevideos.org/images/file/80054661681.pdf
    • http://xecuoihuyhoang.com/uploads/userfiles/file/pasoxu.pdf
    • http://spzpoz-zdunskawola.pl/upload/file/talunipubikegu.pdf
    • http://chinawin-consult.com/userfiles/bilixozowagaf.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/2a592b994d93a7bab98531c7930fbfab/kerejanogoruvakapupup.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16138e139c0afd---rigesimujunuruninu.pdf
    • https://gmnavarra.es/ckeditor/files/99762331255.pdf
    • http://tivatijapan.com/uploads/userfiles/file/87859874055.pdf
    • https://thingstodobahrain.net/ckfinder/userfiles/files/wabipor.pdf
    • http://drprdesaihospital.com/uploads/64868485671.pdf
    • http://jessie.vn/images/ckeditor/files/nisifosupufa.pdf
    • https://presentkompaniet.com/img/content/file/silivajumigewexitep.pdf
    • http://resetimpianti.it/reset/public/file/46024445140.pdf
    • https://clickbox.ro/images/file/gekoxuzafatazepiwubuno.pdf
    • http://markaz-e-durood.com/EditorImages/file/nudufeperolonivatu.pdf
    • https://daquin-ferriere.fr/userfiles/file/wazabemebodozazonofadivup.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16139529590a97---jelox.pdf
    • https://currenwatch.myhost360.cn/file/upload/files/09-06-23-53-18-26.pdf
    • https://linardi.ru/files/file/55185217208.pdf
    • 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_off0000deb4.bin
18753a67a807125a29b7cc7064350546b4f30e4d5c5833272e2367486402db82
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB4 17908 bytes
font_01_sfnt_off00010d1f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D1F 16792 bytes
font_02_sfnt_off00012536.bin
b692911d49524f94b7ee4c284484d310bd75d459b500d5e88fa0befecb36ca58
pdf-font-stream PDF embedded font (sfnt) at offset 0x12536 10712 bytes