Malicious PDF — malware analysis report

Static analysis result for SHA-256 79b33c955c27eab8…

MALICIOUS

PDF

72.4 KB Created: 2021-09-16 22:00:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3b1fce2c4506302287a28d98b9d40c5c SHA-1: 808e6a7453fc766dae0f9480c6598aa1cf195a79 SHA-256: 79b33c955c27eab821c0175501f7278d293290d3d2b47e880f162a40eed41375
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs that point to potentially compromised websites or disposable hosting. The presence of external URIs and link farm heuristics suggests an attempt to redirect users to malicious content, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://crewmak.ru/uplcv?utm_term=rupaul+drag+race+season+13+online+free PDF link annotation
    • http://thaisomboonautopart.com/userfiles/files/buzusezipitibusesaje.pdfIn PDF document text
    • https://tuoitre.bacgiang.gov.vn/lib/ckfinder/files/31484935711.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/161431451812de---zijimalizi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142cd6f57d20---40562485336.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/rurupuwelul.pdfIn PDF document text
    • https://2b3la571ga-70p.com/contents/files/sukojewatapegazafuv.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210907_23ADE1453057E887.pdfIn PDF document text
    • https://netcsemege.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/dixubosifuku.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/40048183402.pdfIn PDF document text
    • http://incomingmakedonia.com/files/files/36027776659.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/42410452061.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/61879351415.pdfIn PDF document text
    • https://stmarys-perthamboy.com/upload/File/jubofuxav.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/8219220802.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/xizugetakinebetatedafeti.pdfIn PDF document text
    • http://okna-kursk.ru/page_edit/_samples/userfiles/files/bipodozalumozetugojux.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/161417c517399b---dogebatuxa.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/wesibaboderiz.pdfIn PDF document text
    • http://meditopthailand.com/file/73364520852.pdfIn PDF document text
    • http://viswinkelindex.nl/images/uploads/wunekazuwipesezutiti.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/84349251528.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/87467184214.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_off0000b61c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB61C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE2E 17044 bytes
SHA-256: 422b3f708d27f077aeb055c3995a80a2f1fca5de8461202f28a84d3dc6431590
font_02_sfnt_off0000fa68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA68 11064 bytes
SHA-256: 4c9dbb84d45714e08d9a035ebbd61ac6d622ba662f448dcf99ba5384f1ecf99c