Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa1c5aa6d991aabe…

MALICIOUS

PDF

72.0 KB Created: 2021-10-06 07:55:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a9e766c255b017a4b1767e48ebf34534 SHA-1: 322afe6fdf7ce2856384b5a740f0ed849311120f SHA-256: aa1c5aa6d991aabe4bfcaeea753232145d3077dea8a6925bb248b71facdc33f0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=middle+names+for+selena
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/03a862c4c75b8d2432299e1712340070/dijujabododebofixodiz.pdf
    • http://www.romanschatztruhe.de/img/files/dexopozafijoxizidigufov.pdf
    • https://fsbulletsandbrass.com/userfiles/files/48702232863.pdf
    • http://lejuriste.ru/files/file/42901474326.pdf
    • http://fertilityupdates.com/userfiles/files/352205990.pdf
    • https://amd-export.com/site/upload/file/winarazemezuluropop.pdf
    • http://weorderfood.com/uploads/files/3277410564.pdf
    • http://stellarp.com/userfiles/files/15141379492.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3ab6a4308---puxiwababu.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/jufemijanikates.pdf
    • https://cissud.it/uploads/ck_editor/files/jebumivadisalomodebes.pdf
    • http://ryukatsu.com/userData/board/file/lolivapogupefofowabozet.pdf
    • http://anchor-m.com/js/upload/files/30898598767.pdf
    • https://sofupingame.net/calisma2/files/uploads/tofatavorakoj.pdf
    • http://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fogok.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/c7460ac298bb370792c9f7ab861bc1c5/6964253702.pdf
    • http://www.herbertvanderbrugghen.nl/draft/vezeriwodozegovelokumuj.pdf
    • http://3colorjazz.com/fckeditor/userfiles/image/sirinurakefevokukosof.pdf
    • https://samsunyapi.com/userfiles/files/goxuzumofemageb.pdf
    • https://distriparkbotlek.nl/userfiles/files/lukafubojarifozolivojem.pdf
    • https://mi-stores.com/basketballtotaal/images/editor/file/93704997605.pdf
    • http://yejiya.com/userfiles/file/9135586885.pdf
    • http://iwilldoit.ru/uploads/files/files/rabewoxe.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b8ed.bin
a0c0ca12f478db5e022754511b4cec853748ccefffd20e23ae4c4ebc1122a6d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8ED 16276 bytes
font_01_sfnt_off0000e295.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE295 16792 bytes
font_02_sfnt_off0000faac.bin
47460da229fdbd1c62e43905e7d90d781af1bce5e2ef1a1e48b72cf920acb0e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAC 10412 bytes