Malicious PDF — malware analysis report

Static analysis result for SHA-256 df832981422c2454…

MALICIOUS

PDF

80.8 KB Created: 2021-09-17 12:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b1023a0462c11efffb47a4863f9f2744 SHA-1: d88d43fce8263c76827e4f4f0b58084ca2a8e1f8 SHA-256: df832981422c2454646e7c541d87045ca9509367ad2b1eccbe3f7dbb2e312d95
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress upload directories, and one directly to `inwebjor.ru`. These URLs are likely used to redirect the user to phishing sites or download further malicious content. The presence of these links and the overall detection indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://inwebjor.ru/uplcv?utm_term=how+to+print+a+large+pdf+on+multiple+pages PDF link annotation
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613506c68d4fc---raxepulobibozidavop.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/kolufovuzekesexi.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/84225069229.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/161398f4b3a2bd---kodovubakitububuwu.pdfIn PDF document text
    • http://goraku-sangyo.com/userfiles/file/86429214072.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/xuniju.pdfIn PDF document text
    • https://sitycare.com/FCK-UserFiles/files/82857484909.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/95143595952.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/kuwawix.pdfIn PDF document text
    • https://85097781.com/upload/files/motujesigozuv.pdfIn PDF document text
    • https://bompentax.com/quangbasanpham/app/webroot/upload/image/files/18145073712.pdfIn PDF document text
    • https://www.lipca.com/ckfinder/userfiles/files/12489863877.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/9f72ce07ac6a7b264bed158b57ffaf25/gamupuzemulilikiruvutegot.pdfIn PDF document text
    • http://akcihlar.cz/userfiles/file/94991407928.pdfIn PDF document text
    • http://chornakorn-packing.com/ckfinder/userfiles/files/putigemujaf.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021091320361173499.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/puboz.pdfIn PDF document text
    • http://agarimo.com/archivos/archivos/89120028580.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134e3d4807e4---xovexibotojerusovi.pdfIn PDF document text
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/7028531345.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_off0000d48f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48F 18424 bytes
SHA-256: 91826327c00169f5144a1304d671ecae419892e6c9959e43e4e65f837398217e
font_01_sfnt_off000103dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DC 11016 bytes
SHA-256: 4d3d3fd19419f3e0189789caca914dd4a630ff5555e408f59ea31d1b358654c7
font_02_sfnt_off00011d49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1