Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c8c3c7e6c23d54…

MALICIOUS

PDF

82.8 KB Created: 2021-06-30 22:07:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7c1fc8f35f4c11315b4d0d2d700decdf SHA-1: 14aaeb068977c0891af8a4990fabc2848e41c5b6 SHA-256: b3c8c3c7e6c23d54af31119b6a9411e8bf0d22b00adcacf3fa11d8a349fabab9
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO poisoning. The document body is heavily obfuscated and unreadable, providing no further context on the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://ienter.bg/files/10695717823.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5c47af787---kilarasalakavisafiro.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0710a8409---18711010697.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce3dde156b---371691541.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/0a8003aa8ffdce6dddc79421db9ea6b5/ravolokunezakalirom.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/2ab6081898923eddaf5eb831110fc463/zuzitu.pdf
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/eccb7869c829eae9beb41a342b162c9e/teravaw.pdf
    • https://hirurgija.me//files/dafogaza.pdf
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/doniware.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782db3df422---raruruzor.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/bn95nu6i744ncaankio06ctdi2/26726491519.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/gjt8csvrfmj7p8glua6eb8eh3j/30868438188.pdf
    • http://davisnewfoundlandfamilyreunion.com/clients/60627/File/levedozakakibofiramonuf.pdf
    • http://footstepfloor.com/upfiles/files/fetisupaxibuzowitinu.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d93dcca611---lubutajadozu.pdf
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/bbae4c80a037cb270615a5ed23f2286b/tativeledivafuzuzulegil.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/8u6e3r66epmefar4alpppgffic/rukofuxux.pdf
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/af551dbf74f403675f1221500e37ca9c/38801535476.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d87f616f77b3f73531a8366ff8e51286/pilojikizelaf.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160ce4ba328cbb---bomurowag.pdf
    • http://wxeina.com/userfiles/files/gariwitogezemivanofuva.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16098c0d88f38d---32792129080.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=the+outpost+bar
    • 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_off0000e1e0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E0 16792 bytes
font_01_sfnt_off0000f9f2.bin
6d0d391e42a064130bfeb97ff9108695932a8d73e7c70baad90bf17dd3cfe97f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F2 17512 bytes
font_02_sfnt_off00012768.bin
a158a39a5ec406740d5ed6964c8ca2405970f86cb9a56a36656fae664d927dc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12768 10308 bytes