Malicious PDF — malware analysis report

Static analysis result for SHA-256 64331d92f91b6209…

MALICIOUS

PDF

87.3 KB Created: 2021-06-26 05:22:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: cec4d0302743ad4a3f6a7dbd7955ce54 SHA-1: 4ffaab35b73c5ed83a1b20a1e992d905242f9db5 SHA-256: 64331d92f91b6209953bca67fabe0d7cdf8723208be0b371b2c319b31bc288eb
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, with high-severity heuristics indicating it contains links to algorithmically-generated URLs hosted on compromised WordPress sites. The document body is unreadable, but the presence of numerous external links suggests a phishing attempt or a lure to download further malicious content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6039c1221a---sesebeduw.pdf In PDF document text
    • http://barudan.hk/UploadFile/file/20210624190534831.pdfIn PDF document text
    • https://apinero.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782d31aa3d1---54359655163.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/149020464149a0c0300db64cd3eb7177/relegiratowi.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160b8525111a44---pofurididurefozawodad.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/f34cfe6371d3a5cc7bb0d0755127a92e/poxukepetawisina.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcfc7731471---44567154940.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/22a93a608ac7e27c7a74a0570c8b2c6f/jetijexuperegoripa.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5042be432---vefobedudojuvafubenezam.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/cf9410384a47112f7c066ed80aa4d827/fozilogegozi.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/770947f31f04ce4a70d7ad8a1d99d9f1/8674523268.pdfIn PDF document text
    • http://tutek.eu/userfiles/file/rinupebajonugagarevo.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087691a7be79---dajediwidejigexosijobivew.pdfIn PDF document text
    • https://chauphongasia.com/wp-content/plugins/super-forms/uploads/php/files/mg332tve2ccdaqeb9o6h1lketh/pebudagotam.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fe063fd90---2452428795.pdfIn PDF document text
    • http://dongfangguohua.com/ckfinder/userfiles/files/35117946870.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca1789e723---fokuxorexogurojiruvubumiz.pdfIn PDF document text
    • https://tomas-music.com/contents//files/30031815395.pdfIn PDF document text
    • http://zigzagontwerp.nl/sites/default/files/file/duziwetusukexegadelufiw.pdfIn PDF document text
    • https://sgpropertylawyers.com/wp-content/plugins/super-forms/uploads/php/files/71e7dd8e444e3fce7a7b36204e362c1a/13212947451.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/28107a3c05d0bd48de0b1566dbbd4b9b/visibikagoxe.pdfIn PDF document text
    • http://amandamaitland.com/images/file/93465145220.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d3ce6a3d924---tifanetiduvusebat.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/75766067714.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/43b2cef7c9b702f15e876d9cf4bb2447/20910692370.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/pojupiduzoxumip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=bendy+sent+from+abovePDF 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_off0000f019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF019 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001082b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1082B 17852 bytes
SHA-256: 856091072f6b387da612fc470bc7f6ba1b05f296428b064bd3b3d7eabca32487
font_02_sfnt_off00013766.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13766 10752 bytes
SHA-256: f7166fb3be6d83e356b4ceaa5caca91ceb1f9e69c75494a4293bdff28daed38c