Malicious PDF — malware analysis report

Static analysis result for SHA-256 28310e5b9886c93c…

MALICIOUS

PDF

90.7 KB Created: 2021-08-25 01:01:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: a921930e6ec82b72321ce070a6f25a23 SHA-1: 393dd7b99ff12f98594013752f5bdcf3be3006ef SHA-256: 28310e5b9886c93c7c0a92cef40a12d29f4c8cff6a09e919f7674fe56f066304
176 Risk Score

Malware Insights

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

The file was detected as a malicious PDF by ClamAV and an ML classifier. Static analysis revealed it functions as a link farm, containing numerous external URIs pointing to various domains, including compromised WordPress uploads and disposable hosting. These links likely serve as lures for phishing or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://garglob.ru/uplcv?utm_term=famous+grandparents+in+the+bible PDF link annotation
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/nexoxefenamewe.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/bb402fe8d6707da2c1f7086b9cda8716/fuzisab.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e7d448475---kutor.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98878044919.pdfIn PDF document text
    • https://kovosluzba-praha.cz/res/file/zazuvudirosotamuw.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/364b79b7c6851a4b2016081616a5b0f1/faxezaj.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/32419991611.pdfIn PDF document text
    • https://geo-decouverte.kenamedia.ch/ck/ckfinder/userfiles/files/juforemolixowejunisukopi.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/45840328205.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/645ffcbd401d77e4b9a68b2ac491d489/dozigatimabuz.pdfIn PDF document text
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/c1d822d2e2f856d63ddf4e880c9c1535/lomokixilaxusujir.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a3dc338865c---78256707400.pdfIn PDF document text
    • http://157.230.241.115/image/upload/File/kavesumoxubomaburu.pdfPDF link annotation
    • http://szentistvanpatika.hu/upload/file/xedoropanizuvumafudidul.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/lunaneramururidazutepi.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/39298415295.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160860ce8a500e---towonupirasekiduz.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/vofalubusobunapipumovatu.pdfIn PDF document text
    • http://lehnerkom.de/images/uploaded/file/leganefosixedenapuvisab.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/5ea72c5b77b3f3492af4f852f9a2adfa/14313936400.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/86660338240.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/53fb8f8eae9977b905f51e4fdfcf43c8/16496421684.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/72564120594.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf9df1756fb---87143015733.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_off0000fe5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5E 17788 bytes
SHA-256: bae3c4dd3510993ac9594cddcd4ec8f8c02d81f07ca4b65a30b458e72c61328d
font_01_sfnt_off00012bb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000143cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143CF 11056 bytes
SHA-256: be45edea22daaa59117d19b6f0ffd0be3ea831521287340a81867a2cf3a882bc