Malicious PDF — malware analysis report

Static analysis result for SHA-256 5809d76d5c1bd58d…

MALICIOUS

PDF

96.1 KB Created: 2021-07-28 07:42:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 4715bc58ee20e3ced1d23d66a6037752 SHA-1: a90d338df32040abca932ff0da15aa8d8dc59f8d SHA-256: 5809d76d5c1bd58d946ccf32c8d0720320e6f7c9d34dc1fde81a54b75369e3d0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which point to compromised CMS upload directories, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues about the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://korean-school.hu/hangul/userfiles/file/7733156476.pdf In PDF document text
    • http://tvkinter.com/file_media/file_image/file/povozodujikifi.pdfIn PDF document text
    • http://md-servicios.com/userfiles/file/mabisaravegesani.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/9vvtid9vkeka2n7lvquuhumn02/44137661944.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/hvs13glckv3qk07qj9se3efj2s/wuwuka.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2fcc63fca---69018355103.pdfIn PDF document text
    • http://mientaytourist.com/uploads/files/suxufisuxamopenisulev.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca0baa97ae---3289064242.pdfIn PDF document text
    • http://yogasol.cz/ckfinder/userfiles/files/33473744440.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b9576bd52---fekidunekunet.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3862a8b5c5---29453179524.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/48942194145.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/5ddaf2af34cb521516b69330b503d240/17652501562.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c888850a0d---82729907805.pdfIn PDF document text
    • http://talleresjpg.es/img/file/wajunukulasekanumebojive.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16073d424de603---24174523435.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1607bef737dc59---88604068096.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/67304007e6dd7211e9e35abcc3623ff2/82504987828.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/79998466554.pdfIn PDF document text
    • http://xn----7sbezcba9a5aggb3j.xn--p1ai/ckfinder/userfiles/files/824062035.pdfIn PDF document text
    • http://barcelonahotel.vn/UpLoadFile/file/18600759943.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16092d1fe3d84f---55243236708.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/906aa71d8f4da3579b46d79c9064774a/46854072038.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+change+wifi+on+canon+mx492PDF 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_off00011403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11403 11012 bytes
SHA-256: 36490cd97a56b8a1d734bfd987a60964c1fd1db08ce53c6ac2a9a644c12fbc74
font_01_sfnt_off00012d9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000145b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145B0 17432 bytes
SHA-256: aa5119385276722d69a77cd138a7cd503ea17b44a2482ceb09645067aa75ce4c