Malicious PDF — malware analysis report

Static analysis result for SHA-256 39531cc90078d70e…

MALICIOUS

PDF

69.6 KB Created: 2021-09-16 14:37:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 346fc9bae8edeac8210f57ab657b677e SHA-1: ae1f0ba4d68aed64f5415f75192b27850a001cdb SHA-256: 39531cc90078d70e35d9f3b4e4850d8d564a3061846917aed3c1c9590d41e945
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple external URIs and compromised CMS upload links suggests an attempt to redirect users to malicious content or phishing pages.

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 https://chcial.ru/uplcv?utm_term=android+11+slow+charging PDF link annotation
    • http://grupafurman.pl/!mag2011/userfiles/file/98426206761.pdfIn PDF document text
    • http://sacmacbook.net/userfiles/file/99463163425.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/57754807887.pdfIn PDF document text
    • http://songdolandmarkcity.com/userfiles/file/27001923547.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/10582695353.pdfIn PDF document text
    • https://phr4u.com/files/debifubexeto.pdfIn PDF document text
    • http://dpsnowodworze.pl/userfiles/file/nazivoredulin.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161417f954db2c---78108937300.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613edd22c82f4---kubunoverul.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/xotel.pdfIn PDF document text
    • https://ngaa.org.au/application/third_party/ckfinder/userfiles/files/67690198344.pdfIn PDF document text
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/lejozilozebafuzusasulozig.pdfIn PDF document text
    • http://vetsnab32.ru/userfiles/file/95224778038.pdfIn PDF document text
    • http://forspeed.cz/ckfinder/userfiles/files/92355934879.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/lebid.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/xetor.pdfIn PDF document text
    • http://www.siphonicflowmandiri.com/upload/files/jubasuwujunopu.pdfIn PDF document text
    • http://quranday.org/userfiles/file/39433119506.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/65585634093.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/kenefusimobubere.pdfIn PDF document text
    • https://isleo.com/i_photos/file/67527629660.pdfIn PDF document text
    • http://xn--elementy-zczne-kwb98g.pl/media/file/dewago.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134c0e6ea8d7---xuvuwiwefovemalexu.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_off0000b233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB233 15276 bytes
SHA-256: d4957f600f0866645787d25ad890fc84d07c0b567f026522575d8adfc93fa642
font_01_sfnt_off0000d893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD893 10540 bytes
SHA-256: cf6b8eae9f0b7fa2a7008b8e28ba82a7e93f27272a959dbb526748ebf75303db
font_02_sfnt_off0000f068.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF068 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1