Malicious PDF — malware analysis report

Static analysis result for SHA-256 b31dde08a8b3b155…

MALICIOUS

PDF

91.4 KB Created: 2021-07-26 00:29:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 681a07aa5fd8758cbc340a7196e70199 SHA-1: 60c34a915b2b891ff867a6a206966413cc226a1d SHA-256: b31dde08a8b3b1550a4af5174d0559f1232e7128e474d9b81bfc65f94a7fbf49
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, suggesting it functions as a link farm to distribute malicious content. The embedded URLs and the nature of the heuristics strongly indicate an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://kisikana.hr/UserFiles/files/12330273667.pdf In PDF document text
    • http://bhttourist.com/upload/fckimagesfile/balopedoxufemapusejep.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8c6492c3a---rofomilos.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b56347d0a09---fazixepi.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1677023ec---38949514774.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/234f487bc2098d2a817ce94dbcf3a52f/samisivaguxo.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac71c391009---wugenudamegomogojekax.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076602497f7f---31734397175.pdfIn PDF document text
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/jipegilaba.pdfIn PDF document text
    • https://dolmalatrek.com/userfiles/file/waguzalusazoji.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/9dfe336a91d33a3b9135635d4222a703/wodufalesupakixovof.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/27366503186.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/2e5901940d2ec780e5d09b97866be90e/13902899577.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c111c894881---56922114374.pdfIn PDF document text
    • http://charivne.info/images/file/deromamudigexo.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/61c23715d5b8e48b3eb623f4cd7261e7/jugusawi.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607104ab39698---xukagokurasemavuki.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c583e7a78b---68238252128.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/46762136597.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3d2e2082e---36243032820.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afc3995cdfa---3874061345.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d08aa0873d7---pubitew.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/12897636799.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091d9200ceb6---74122047282.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/muzaruwukunafipogiduduwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=fahrenheit+451+movie+director+michaelPDF 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_off0000fc9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC9F 18800 bytes
SHA-256: e57bc175fc23c7bbfe260cb0d494d813161fe9a76547a9d6c99903b8a42d5bcb
font_01_sfnt_off00012c4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C4D 10772 bytes
SHA-256: c886184df8e89d68e41e9d356f9a0230d367391db64c9bdc4365d1965330fae4
font_02_sfnt_off00014507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14507 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1