Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa15f1239da4fa5e…

MALICIOUS

PDF

91.3 KB Created: 2021-06-29 23:14:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: cd6820c7967ff1909f54333c1ceb0762 SHA-1: ed8def68ebd1f01fe027a7ab2ccebac656a7ae31 SHA-256: aa15f1239da4fa5e0be6389342800ab52edd09f1737af7250411d24ddbe2fe8c
156 Risk Score

Malware Insights

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

The 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 pointing to compromised CMS upload directories, likely serving as a distribution point for further malicious content. The presence of multiple links on potentially disposable hosting further supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/91f95bb0af7d6cbb20690267cb5003de/7338463032.pdf In PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae053cc2e4a---58450222023.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/871baa38efb489160a2c1f06352825e3/xemevex.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608d8ad9a018f---12783647515.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160704998a8a6c---81010746760.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce69f548cbb---purafotojepanemikuvibitus.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c808d8ae06---vopigi.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/53978916375.pdfIn PDF document text
    • http://haithuanphat.com/uploads/files/mifuti.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf2f739da4---79001075968.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a702a21ab66---67350703251.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16077fd0ebb198---dulufolavikazofamafibafiz.pdfIn PDF document text
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/d4c90dbe6b6638caf47c9ea4f2290a3d/67898591438.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087f996919a0---71333169515.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16077c4a74286b---sufewapasesinufemikanewis.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/339qqrh7rp8j0n6p9n69fosei1/96230746939.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ef156cbea---pejuke.pdfIn PDF document text
    • https://carea2plus.com/wp-content/plugins/super-forms/uploads/php/files/d41bca37e9c8fe2824546689d56e0ce5/mebasaroxorunafadetedox.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/58716722443.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc8ebad9c6---4068661885.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/gozupolux.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/nipof.pdfIn PDF document text
    • https://gamasteel.net/userfiles/file/bolelolujitakijuvifole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=ecg+changes+in+right+ventricular+hypertrophyPDF 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_off0000ff17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF17 17968 bytes
SHA-256: 6b8502ce3f90587d7d30329a18586e2b735ef66bce26dcebf7b5679219759e1e
font_01_sfnt_off00012e41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E41 10916 bytes
SHA-256: de7343ccf54ca214bbc4ad3afdaefb56a3a6f73c79975d9b76d4c4ebb9a4fccc
font_02_sfnt_off0001478c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1478C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1