Malicious PDF — malware analysis report

Static analysis result for SHA-256 1aab66f0f181fd63…

MALICIOUS

PDF

80.5 KB Created: 2021-09-21 02:28:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: da6b44c07aaa4144344577a16b3a1455 SHA-1: e8369619d4a3d82cc52fafdbe8289b09271396fc SHA-256: 1aab66f0f181fd63fe92035339fa32c82b8f1f4586068a0ac74bbc5f1f95dfa8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous URLs, many pointing to compromised CMS uploads or disposable hosting, characteristic of a link farm used to distribute malicious content or phish for credentials. The PDF structure itself does not contain executable scripts, but the embedded URLs are the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://amicissiapiemonteisa.it/userfiles/files/57345219301.pdf In PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613eab65ee942---35689154931.pdfIn PDF document text
    • http://stilistspb.online/public/files/uploads/files/lulatibonexopo.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/janitufopofido.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210909_838B966DBD6160A9.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210908131148.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/zezubitawug.pdfIn PDF document text
    • http://pdww.ru/ckfinder/userfiles/files/lamuve.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/texufusapuwa.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/sobetixekinebo.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/32403673894.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/duvexet.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1614855782e5a7---vodude.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/565a4421ffe344d64378362520bd05c3/nekasenixe.pdfIn PDF document text
    • http://steinbach.casawell.tw/userfiles/file/vijako.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/lufajiwegeziki.pdfIn PDF document text
    • http://irinabailey.com/upload/files/zekow.pdfIn PDF document text
    • https://www.mnogotrop.com/ckfinder/userfiles/files/warok.pdfIn PDF document text
    • https://premiersuli.hu/files/files/66210483988.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/95563ad1061b58eb55f2d19a2e01aba9/45181437295.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/83640803869.pdfIn PDF document text
    • http://wpchkg.com/upload/image/file/63548486448.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/62446563927.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=hyperbole+in+a+sentence+examplePDF 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_off0000d48a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48A 10884 bytes
SHA-256: 1cfa3d1b82f9a2e0408620f0bb223a747734c5d3bc0cf387cf67dccf8c122190
font_01_sfnt_off0000ed70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED70 18280 bytes
SHA-256: 251acff3ab0a9fc29a783c0278839aef58a7c80adb964e07e42b151ec7630dd0
font_02_sfnt_off00011c9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1