Malicious PDF — malware analysis report

Static analysis result for SHA-256 31343c362530a4ee…

MALICIOUS

PDF

72.4 KB Created: 2021-09-11 08:05:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7d640d923f7f814503c67bfb418b49f5 SHA-1: 919b785e75f49b1ea4b4b61c6e59ad2cff80a4d1 SHA-256: 31343c362530a4ee93fd3101770b5ef001755b46da9ade78d712dcb4b1ea4806
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it is not intended for human consumption but rather as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://coretry.ru/uplcv?utm_term=what+is+a+phone+launcher PDF link annotation
    • http://bilafafafa.com/shopadmin/upload/files/78490562703.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/buzunumonuxoririzizubalu.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b492d872bf---kedomopisu.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/29072514574.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/90819402462.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff5008135d---10083915018.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/161303b9752968---26337573574.pdfIn PDF document text
    • http://anadolumatbaa42.com/genelresimler/file/xuxonajexinido.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a2505c9fda---53825654042.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/11352089152.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbdf97ef42---54284497172.pdfIn PDF document text
    • https://latework.cz/soubory/geberemesazejop.pdfIn PDF document text
    • https://amgaa.org/temp/files/rupusajajomomelifu.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/zolimok.pdfIn PDF document text
    • http://servis-hradec.cz/files/file/nadugivekifafininam.pdfIn PDF document text
    • https://spvi.cn/filespath/files/20210902060809.pdfIn PDF document text
    • http://islenapuntos.com/campannas/file/23864133986.pdfIn PDF document text
    • http://csc-028.com/userfiles/file/20210909171848_3uejrx.pdfIn PDF document text
    • http://esistore.be/userfiles/file/fijukup.pdfIn PDF document text
    • http://gabortech.com/admin/file/jebavipagerimelagenerejuv.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/161322fe7043d2---43057725589.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_off0000b95f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB95F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD176 10564 bytes
SHA-256: 7d6b2ecb1da6b5e85779e099eac59e017a33b429eb7f6a35f2ae85ac90bc9215
font_02_sfnt_off0000e98a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98A 16752 bytes
SHA-256: a4b2635c67c21e102deb7614ca5ae2bac6ef2de10e7cc2c46bb50688d32c1046