Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb8fc14d887912ef…

MALICIOUS

PDF

81.6 KB Created: 2021-08-10 15:07:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 502e44feae549757b45609c5ab080a8d SHA-1: 13bfdbf5f4253910150ba586c7378605c4e1a1bf SHA-256: fb8fc14d887912ef69c289df0e3c07d3569d01df50cae6a1001479b27369af0a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, indicating a link farm designed to lure users to malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

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://smidgel.ru/uplcv?utm_term=radiographic+image+analysis+workbook+answers
    • https://porterbrothersltd.com/app/webroot/uploads/bubel.pdf
    • http://mvclassof1990.com/clients/8/8c/8ca0ba2c7a07c5cd1f21f9fc323c16c5/File/43957312395.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609066af5ee2e---papemejego.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16099b83384a3a---tibole.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160e43595e042a---95049461448.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/d1b20dccfb0e166d20026f87fcac57df/45220110992.pdf
    • https://xetnghiemadndanang.com/upload/userfiles/files/88680035846.pdf
    • http://beautybybelief.com/admin/images/file/45576068875.pdf
    • http://teusz.pl/UserFiles/file/54959786421.pdf
    • http://dambi.pl/userfiles/file/98556124659.pdf
    • http://orikon.net/Images_upload/files/xopofazojakufonubipozin.pdf
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/8c8067376fac91124adca3122c9240c2/jozakodilapaz.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f98d1265e0f---kapoxutupiroxamov.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fac89de67b---ropij.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f8eba6af1a5---bujudutaf.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd74a483fd---lujimisufeke.pdf
    • http://naturabliskociebie.pl/userfiles/file/23984878676.pdf
    • https://artenika.pl/fck/file/45643277048.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/5f633a38451861eb26c017f589bf78f1/pudujifewufagasu.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/1de84d604f760452949960c722ea8d24/gipavuxopazijevifun.pdf
    • http://bundoreh.com/fckeditor/files/file/biraterujig.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090c34b41e78---pemanapipef.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/c56b860482098f19c398a631333300d0/94478042120.pdf
    • https://bookscollection21.blogspot.com/?book=0323522815Learn
    • 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_off0000d932.bin
92e3f2032036b67df219f9c52f2672835d851b05e424efc89a6a2fc1e6daf6af
pdf-font-stream PDF embedded font (sfnt) at offset 0xD932 17892 bytes
font_01_sfnt_off000106cd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106CD 16792 bytes
font_02_sfnt_off00011ee4.bin
c861c5b3a388de64479d52ec87efd40a75717f6f5e0c8dbc1666ac2641658470
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EE4 11340 bytes