Malicious PDF — malware analysis report

Static analysis result for SHA-256 a32836f0e40d55af…

MALICIOUS

PDF

86.1 KB Created: 2021-07-24 12:44:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: e70cf8cb4e6a473e1ba7c0fbd3ec2bf0 SHA-1: b3af9b23bf8e411a90e183b6fd4d7d1d62b03ce9 SHA-256: a32836f0e40d55aff94ea63b244dbc1ed68b3c080ccb8149e57c7ec7abad9388
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, suggesting it's used to distribute further malicious content or phish users. The PDF structure itself does not contain readable content, but the embedded URLs are the primary indicators of its malicious function.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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.
  • 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://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/bd6af00b675d279b1c03a3082314684c/mefewinuzaditaxovimune.pdf In PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/d94c5a24ot2n81iu15gprhlbth/97196976507.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/jeruzogokukiruponato.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/xokijuboranuwabazidubejul.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/35204772810.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/19fe994a367f876d538cc0c1260574c2/tamufesomal.pdfIn PDF document text
    • http://ghhs1968.com/clients/5/57/5762190d0a265df614d1f295a7060a42/File/wedizikelisenelijowunewi.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/35039724530.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608d77f77b001---32068086002.pdfIn PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/63985816279.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/5cd03a96349a3dcb4fcc52dee52c5cb3/farigobefevupu.pdfIn PDF document text
    • http://dr-onesrl.com/userfiles/files/50127844236.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d56eb09a0e---1329940764.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/vuvajufenadodokukifokino.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb4f815d03---80446947227.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f98b8527f85---wawolixobapivab.pdfIn PDF document text
    • http://elhammagazine.com/ckfinder/userfiles/files/1787066787.pdfIn PDF document text
    • http://ikra-ekb.ru/files/fckeditor/file/32261128324.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/08uahft8ggji9mqogvjfm9uekc/14270286086.pdfIn PDF document text
    • http://nhs1966reunion.com/clients/1/1c/1ca8f1639ee69cd7806809ed3bcda9bb/File/68298963811.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092512091299---veresisafimegugelujumane.pdfIn PDF document text
    • http://candientushinko.com/images/file/sufamofew.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/95953729776.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/bc930b5a90889b278fa87710d2843efb/zexusowitejakan.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/96908688562.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+to+take+superheat+and+subcoolingPDF 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_off0000ea22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA22 17292 bytes
SHA-256: 4e556d914cb064ac57d87eedd3633a6e0e0ee2487e6c9d9189039609e2cca3d6
font_01_sfnt_off00011778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11778 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F8F 11200 bytes
SHA-256: 3502cb7cb116c5f94b1b5b081c581b3847f985b78e0f9c6da8591da005906a50