Malicious PDF — malware analysis report

Static analysis result for SHA-256 f28b3fbf508e471d…

MALICIOUS

PDF

80.5 KB Created: 2021-09-03 12:42:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 38c165f4ca817849970ee77a590d956c SHA-1: 4f2716890e3aee1cfe0609b0b64ab2dcb066c9ee SHA-256: f28b3fbf508e471dbbc8d03f7e7a48757efaa5f692b70d838cc8be306c75dd71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating it is likely a phishing or trojan distribution attempt. The embedded URLs and heuristics suggest it functions as a link farm, directing users to compromised WordPress sites that host further malicious content. The primary attack vector appears to be luring users with a seemingly legitimate document to facilitate phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://medvor.ru/uplcv?utm_term=jurnal+bpjs+ketenagakerjaan+pdf PDF link annotation
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce77b1f3e7---27398731378.pdfIn PDF document text
    • http://neoneophytou.com/ckfinder/userfiles/files/pobemajujasawore.pdfIn PDF document text
    • https://tecnomatec.cl/upload/file/92480340757.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/18884450996.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160cf8782828e8---69700360188.pdfIn PDF document text
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/63837691794.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/7adb670da537683e0d98db4bde1467e3/26060920984.pdfIn PDF document text
    • https://terrebleue.org/userfiles/file/67611500943.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/wakeduzurazukubuvuse.pdfIn PDF document text
    • http://fernandopelosini.it/userfiles/files/dafogenan.pdfIn PDF document text
    • http://mosjob.ru/images/file/gekig.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/sepefianm2m3ib1e11fohjdo2f/folur.pdfIn PDF document text
    • https://phnews.ro/files/file/lujokidededusegazidimez.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078fedbc08b7---67008270090.pdfIn PDF document text
    • http://fisioterapiasuzzara.it/userfiles/files/25741185313.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/pukatufarasekuguxenumi.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/2sb7hn7grnp2paa5a1pjl7i677/wifexopuluzukumekiwuxiso.pdfIn PDF document text
    • http://parkwaywest1974.com/clients/861606/File/57252910976.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/78054616834.pdfIn PDF document text
    • http://caryhigh1987.com/clients/41333/File/jefomibi.pdfIn PDF document text
    • http://insidethedigitaltrend.com/userfiles/file/lemakidokupaf.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/nevupisuz.pdfIn PDF document text
    • 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_off0000d49b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49B 18108 bytes
SHA-256: 58b3ce56a0504a25c51dd6fcb4e39b2726938b4d98fc5058d25854fa80d86887
font_01_sfnt_off0001039d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1039D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB4 10916 bytes
SHA-256: 7b42b2d4d892758132d136706140bbb194fc378149a66ab364422a987171bbe4