Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f80a6523f8effd…

MALICIOUS

PDF

83.2 KB Created: 2021-09-07 23:19:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bd1231be29e4d923f3bdc07749d90ecd SHA-1: 214a8fac2357bedec5a9b167fc4b6684b36349ab SHA-256: 83f80a6523f8effd98cd84702630c847f37d0f34d58e0a62f66054ee8f54c6d8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://edu-family72.ru/content/images/uploads/file/95721462297.pdf In PDF document text
    • http://xn--42c1dhzaq5aeb.com/userfiles/files/jefarifese.pdfIn PDF document text
    • https://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/vopobonudivitifidemafis.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/upp5h4kkj2glj8nqt24lc17vee/99345538536.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/98944239996.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/60217415758.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afdaf9d642c---76216170925.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/93712070402.pdfIn PDF document text
    • http://ruihuitax.com/files/file/ruluzupefexotowugomiz.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160852372abd90---xisegig.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/76568011294.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/84579917697.pdfIn PDF document text
    • https://betenenergy.com/sites/default/files/file/zoluxemakuvufesivibuz.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dac3c2e082---rufumokivasevabav.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/37187407881.pdfIn PDF document text
    • http://asirakademi.com/resimler/files/11412159466.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/deledaligu.pdfIn PDF document text
    • http://fedoro.ru/upload/file/80868259787.pdfIn PDF document text
    • http://euro520.net/userfiles/file/16264917011398401290.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/75253980503.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/0acc47d19aac7182a036e3f2d4de4877/kugomet.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c75da27c52c---73357732010.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4d9b20ebc---35541366496.pdfIn PDF document text
    • http://rfinshaat.az/userfiles/file/lisavobotura.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/milupavabomup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=vic+dicara+books+pdfPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/tuxodevigomeliroj.pdfIn PDF document text
    • 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_off0000e00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00B 10436 bytes
SHA-256: fe19c787dc889c5de400169e1b2f88051e4d2de6ac4aa2bdcc82ea7203b8be8c
font_01_sfnt_off0000f797.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF797 18088 bytes
SHA-256: 37966545628ab3e70572c619a09f326c9c043ab0027531baf39bbc4684a6d14b
font_02_sfnt_off000126ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1