Malicious PDF — malware analysis report

Static analysis result for SHA-256 1df512d6c8b10d29…

MALICIOUS

PDF

89.2 KB Created: 2021-08-08 06:59:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 494659862fcff9000e11a828efc30cfe SHA-1: 328ca5bc08b3fcd4f2b4fb79e777ee94204abad0 SHA-256: 1df512d6c8b10d29b70e659bb8fcde9b5ae05835b93202d0791db9dabf296b7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress upload directories. While no scripts were explicitly extracted, the nature of the links suggests a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5f44c3010---zaverav.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2121c9210---fegiwoxug.pdf
    • http://kursadowicz.pl/Upload/file/gudikule.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba294eef3d7---xutabenuxu.pdf
    • http://mcutech.net/upload/2021/07/file/16255327961223657624.pdf
    • https://europawindow.com/app/webroot/img/main_content/files/16664635617.pdf
    • http://spakimthi.com/upload/files/novenesafisopirupetug.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/12ff8a5322a7e3a676c033bb88c957ca/vevebabojibexalimipozeni.pdf
    • http://fittbike.hu/files/file/34367718232.pdf
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/4687366041.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160863d77598bc---81756171856.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/89f4303852a7a92ca0fb2642974361e2/77354071708.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cecadeef5---42710229656.pdf
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/68782122465.pdf
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/85969377278.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/bd4e69433f1ad331439ce14062e6db43/1147606641.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac6cd5ef37a---27932529093.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/0182307348a9a80ece7e9f66e288b354/loxujamotizevuf.pdf
    • https://xn--80aanugxqi.xn--p1ai/admin/ckfinder/userfiles/files/74645409112.pdf
    • http://vencedor.coop/images/admin/file/37569018810.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c68a5f0bb---68139835984.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=should+i+put+job+shadowing+on+my+resume
    • 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_off0000f62e.bin
b8c0f63b9c41d9deb6fb991606a30e5cabf138dd7db14d1cc6ba6ef0361b57e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF62E 17976 bytes
font_01_sfnt_off000123ef.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123EF 16792 bytes
font_02_sfnt_off00013c06.bin
191bf493f84e8978441f70ee328db114bf56ab5c9d39d49df710ac529c0efbc8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C06 11484 bytes