Malicious PDF — malware analysis report

Static analysis result for SHA-256 b739b944441be5a8…

MALICIOUS

PDF

73.1 KB Created: 2021-10-01 14:27:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: fd384d02bfefdaf023063bc386bd86db SHA-1: f787cffa11b897734df923d0e97d243407388f33 SHA-256: b739b944441be5a836f1582559f38967316e455676dbfd467a89b495166aa29a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple domains, suggesting an attempt to distribute phishing content or malware. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://dalboncostruzioni.it/userfiles/files/19432223216.pdf In PDF document text
    • http://yuhenganquan.com/userfiles/file/20210908030457_1024701757.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d3eb1d8eaa---kojikutimubebu.pdfIn PDF document text
    • https://petribax.nl/userfiles/file/97934292972.pdfIn PDF document text
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/21660596851.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/wubowudozojojivo.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/potufadixixagebabikuv.pdfIn PDF document text
    • https://beamstraffic.com/amb/userfiles/file/piralivubugewomu.pdfIn PDF document text
    • http://kbcsisa.com/upload/fckeditor/file/95571725350.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/sotilepiduwoxosubot.pdfIn PDF document text
    • http://ezicms.antifftech.com/uploadfile/file///2021093016323373.pdfIn PDF document text
    • https://drticket.ir/basefile/drtiketcom/files/655051693.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614d2d24b6ed1---bidul.pdfIn PDF document text
    • https://exam11.menapoint.com/app/webroot/upload/files/kuvir.pdfIn PDF document text
    • http://tsutae-f.com/js/upload/files/74032884318.pdfIn PDF document text
    • http://sasnowosielski.com/ckfinder/userfiles/files/mumenemesev.pdfIn PDF document text
    • https://mytopics.it/uploads/file/51809275969.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/finituxezino.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/de2885edc054fcbc9dc8c496322b8b1c/905742636.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/pibejodegujewebaxota.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/zemilikisijusa.pdfIn PDF document text
    • http://bilateralmatters.org/userfiles/file/guxirolage.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=mr+robot+season+4+123moviesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB460 10844 bytes
SHA-256: 9330eab60f177e14354136e26ec68276125ae4f28cdff1988505d99240b31bcb
font_01_sfnt_off0000cd97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD97 18220 bytes
SHA-256: 7c9a3aeebe5b0df5f13a39fde32f5b5fadd33d95b8d92cd30ee6039206e774f9
font_02_sfnt_off0000fd04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1