Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ca5f34ef1dfeb8e…

MALICIOUS

PDF

90.1 KB Created: 2021-06-26 22:24:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0453801c437e5c9ca832fa960f7a206b SHA-1: 831d2529b8e90ad67e2508d0e635a2136015f732 SHA-256: 8ca5f34ef1dfeb8e9f421c1a924f6f3568cba4280b560c24835cffbc7e10713c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1c79e785b---wibunademun.pdf
    • http://ca1970.com/clients/10044/File/82798990277.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b85540180a5---36587645527.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb418c7784---pezekajoziwad.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b5d4f2ea0b2---15929170104.pdf
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/75be6243e1e4147962cae7f03a8c124b/giniwijuvugemegilinet.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070ce1a424a0---68527760128.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7bdefc3588195a4c491d86f4af7788e6/buxuxaxujepisat.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acab8672162---tenosifaditenilu.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/223794aa5904c485430ac6d60efea7b4/nemavuriw.pdf
    • http://apcmagon.com/userfiles/55375271928.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b31974902d---vemadivupezojotirole.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e2d8673f6---namomuwosomesizixadigun.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/30908525828.pdf
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/607d11d9d007a499d7127d0b7d2bd51d/96517397651.pdf
    • http://huntland.hu/upload/file/bumuxepuvozixazajowaku.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607cbc0e54df2---16410560762.pdf
    • https://twfern.org/upload/ckfinder_temp/files/20210626144637.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab8d38c3796---94692661206.pdf
    • http://leebyunghun.kr/new/upload/board/files/77213826457.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0c9164fc3---66304017725.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adad2635ace---lewukuretenuw.pdf
    • http://notarbrazda.cz/userfiles/file/pabosop.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5bbd8451c---59349237497.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=scriptures+on+growth
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/4e48a94050873342ed3c18c84d57a182/73145055065.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_off0000fe94.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE94 16792 bytes
font_01_sfnt_off000116ab.bin
f076128a3f9414014f6ea0fe9ea66c269592afa9f1a586e49466ccd9bb9bb71c
pdf-font-stream PDF embedded font (sfnt) at offset 0x116AB 10708 bytes
font_02_sfnt_off00012f3b.bin
1a67c73e71cc6e716047025c96639b8c61a9c10c8dc1c5f6e97751cca1219387
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F3B 16852 bytes