Malicious PDF — malware analysis report

Static analysis result for SHA-256 8af8634d5531447c…

MALICIOUS

PDF

81.6 KB Created: 2021-10-05 18:26:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 694450c607ec1e89e6c3207252ca179b SHA-1: 4a49ae86d53d5bce7a6a0f0c2eee7f19b3a316c5 SHA-256: 8af8634d5531447cca902785382bad54d83538455c379ac0746cbe505a82d8e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, hosting numerous URLs on potentially compromised or disposable domains, designed to redirect users to various external sites. The presence of PDF link farm heuristics and embedded URLs strongly suggests a phishing or spam distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://younewstoday.com/task/userimages/file/46284465183.pdf In PDF document text
    • https://silverbirdmarketing.com/pages/images/file/dopavaga.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/jasatabowatox.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/33478375370.pdfIn PDF document text
    • http://phayaotechno.com/UserFiles/File/lakometudumegujomil.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/zazibapikozomin.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/68725592807.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/52102246798.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613428e0ec67b---bidilawokuludurabaxubavo.pdfIn PDF document text
    • https://florerialafloresta.com/ckfinder/userfiles/files/mirixokalamevi.pdfIn PDF document text
    • http://zxpgw.com/userfiles/file/4185083166.pdfIn PDF document text
    • http://tvsatkrosno.pl/userfiles/file/talabupudud.pdfIn PDF document text
    • http://jgweld18.com/UploadFile/file/20210903021350456.pdfIn PDF document text
    • https://koratspring.com/upload/file/dakibirube.pdfIn PDF document text
    • http://zoldjogsi.hu/uploads/files/vasidariki.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/8991231960.pdfIn PDF document text
    • http://foodvellythailand.com/upload/files/47403872341.pdfIn PDF document text
    • https://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/44978152654.pdfIn PDF document text
    • http://gsprojekt.eu/userfiles/files/talajej.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615c1fc0aec65---dikiw.pdfIn PDF document text
    • http://sloplast.com/userfiles/files/10727340110.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/c1c572e1dd0bfe02248d2094384a5661/71877017163.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202110030551124413.pdfIn PDF document text
    • http://evopizza.lt/ckfinder/userfiles/files/wifaz.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/80881213821.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=biological+clock+theory+of+agingPDF 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_off0000d7d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEB 10704 bytes
SHA-256: 9d10e236fa380c173444c5ae7513a5871b84511703737c37129eee1ea34979ee
font_02_sfnt_off0001087c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087C 18616 bytes
SHA-256: 8aa9b69c10119caa4438fb1159a9849d1cb49d83e54bc09058fa000e9d1a1db0