Malicious PDF — malware analysis report

Static analysis result for SHA-256 87179e1da98c32d8…

MALICIOUS

PDF

90.6 KB Created: 2021-07-31 08:24:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b5af38c6f4a6b0fc2b3a933d831acfd0 SHA-1: f237307718a2bfe43623403339d02dd39ee3ec83 SHA-256: 87179e1da98c32d87ea382161aaa9fd3bc0290cf18f6a6181995a848e4e1e258
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs that point to other PDFs hosted on compromised websites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The file's structure and URL patterns are consistent with a spearphishing attachment used to lure victims into clicking through to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e9da352e5---37576775271.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/1cb24ade1351aa19762a2d066bdbeb00/mutiduvi.pdf
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/37625910488.pdf
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/mejuxebomal.pdf
    • http://korsorlampang.net/user_img/files/95770674846.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16089922e154ca---kigisosakobupuma.pdf
    • https://biovuspharma.net/userfiles/files/parulunobuwitedasanoja.pdf
    • http://okfilm.kr/userData/board/file/14505516690.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2bfa55a3e9---84974611047.pdf
    • http://bularz-auto.pl/images/userfiles/file/29344377997.pdf
    • http://bazis-expertiza.ru/ckfinder/core/connector/php/files/mizijiku.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/b58e03db9c8737dcbf6bcb4ed31ed80e/43511996856.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607316baafdfc---rururige.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/fab0ef5cfb55dca169669bb5e8def39a/51512559586.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6f999be9c---totitijor.pdf
    • http://incucinaconalberta.com/userfiles/files/vosuwurax.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/a2a6c1acfa4970b33e430822db7c7dfd/15269905213.pdf
    • http://www.golfusa.be/userfiles/files/turogozofozabuzisozibugab.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b67b16f4a---tobumetipu.pdf
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/77852794686.pdf
    • http://bebsulmare.com/userfiles/files/72303358290.pdf
    • http://changrung.com/ckfinder/userfiles/files/bunitimetoset.pdf
    • http://tillmanfamilyreunion.com/clients/b/b7/b7385abc5988d1ee605fea7695e3d00e/File/54120846920.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=english+in+use+3+eso+extra+practice
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e907.bin
d0629cc641092ad9ce0a51a86fd2b28f67700e9105f39e196ff916f8f11c8bb8
pdf-font-stream PDF embedded font (sfnt) at offset 0xE907 11008 bytes
font_01_sfnt_off000102a6.bin
3f30313d6b69c6009a59ac801e528448c3117aafc13732dd0118d77f50969ae6
pdf-font-stream PDF embedded font (sfnt) at offset 0x102A6 9036 bytes
font_02_sfnt_off00011570.bin
62523273d3a2358b74d72aba34b57833afdd8e2b4dfdbed50941ae7b8d905a85
pdf-font-stream PDF embedded font (sfnt) at offset 0x11570 18136 bytes
font_03_sfnt_off0001438a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1438A 16792 bytes