Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d5457b764b02eea…

MALICIOUS

PDF

96.7 KB Created: 2021-07-06 01:25:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a35532ecf83de9dbdf6e8da5b8b1765a SHA-1: f17540aed03689736b4c501b2eb812f421941763 SHA-256: 1d5457b764b02eea7eefa906b468b9172b79e6f1f21a5ad7b7c37c390bc0b1db
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. The PDF contains a link farm pointing to numerous compromised WordPress upload directories, suggesting an attempt to obscure the ultimate destination and potentially deliver a second-stage payload. While no scripts were explicitly extracted, the PDF structure and link farm indicate a phishing or redirection attack, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9910

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 http://boothbayharborshipyard.com/userfiles/file/nufurolirujuguwa.pdf In PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cb8dc31052b---butedojiwugok.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/efa6161bd955b0f42002c971cfb1efe5/16988626130.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///ginawosifukilelezutitik.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607189d44c6e7---ditodofebavufakebafimedo.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b8b917720---92968460585.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1e92df832---risosevebuna.pdfIn PDF document text
    • http://bjsprt.com/uploadfile/file///2021070212011092.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/dodivavuxawufife.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d75fe2436---korebilekobigagaxunomo.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a82d1201d22---79515256517.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/61592121937.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160753ff5528fb---74126877868.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/vud3n61lt3hbe7i9mtaf09hgn4/41114364823.pdfIn PDF document text
    • http://suseefinance.com/userfiles/file/4630512083.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210520014526156.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16095c13ea5d67---68204421992.pdfIn PDF document text
    • https://gannat-ltd.com/userfiles/file/lakagatupejimalamunuzi.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/fbf567f3e5e102448674b60d70574df4/noxazadiduwomedadisudize.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/1609e598643842---xokigojutipufir.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf710eb3d6a---wikeguwudi.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/55627937603.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160751c478f279---jibaridekipubetosojasuvej.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3d9da274b---vatatuxilanatek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+get+any+knife+csgoPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5C 16092 bytes
SHA-256: 9d5144547e0b729630886a3ad3ce48e7da84b0115899dd9c2390406af6f0fecd
font_01_sfnt_off000112a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AB8 10648 bytes
SHA-256: d73c95d219027dc9eb5284c16df5f1bcba6d8a6bc31fff4d3789a0be48ca9ff2
font_03_sfnt_off0001434a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1434A 18760 bytes
SHA-256: 6911864b25cb64596ab17c3c9d3efacfd4de94a44fad9ea48b2e08d4b7b3ae63