Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8c47598177ef2e3…

MALICIOUS

PDF

74.7 KB Created: 2021-09-12 14:08:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 88d20c7630aeb4fe5892a7c728f52f74 SHA-1: 7892e793949a332f4e50a6ce64f36a38b539de13 SHA-256: a8c47598177ef2e331649124d17891d4cb6ca07b2c6f1a7465436e56b32ad9ed
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for malicious PDFs to execute code. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects the user to a URL such as http://jualumnitoronto.com/editor/uploadfiles/35825460109.pdf, which is characteristic of phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9757

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
  • 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 http://jualumnitoronto.com/editor/uploadfiles/35825460109.pdf In PDF document text
    • http://p-itos.net/admin/userfile/image/file/boxigomeve.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-6/20210906192649203508.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/85491430112.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/pejefiniru.pdfIn PDF document text
    • http://ozkayalarlojistik.com/userfiles/file/15094635596.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/nomeporimubigatu.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/reroxijedonanofobun.pdfIn PDF document text
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xujomumuroranaxipazuwow.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/50904505053.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/97668633324.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b067870310---6320116501.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/tagaxavuvekutesoduz.pdfIn PDF document text
    • https://kotypsy.pl/ckfinder/userfiles/files/75061283781.pdfIn PDF document text
    • https://laflammerouge.ch/userfiles/files/lesonuzuxadajaxenawagilut.pdfIn PDF document text
    • http://1-sanya.com/blog_images/blog_/file/75486332938.pdfIn PDF document text
    • http://mp-journal.com/media/file/46710058188.pdfIn PDF document text
    • http://parfumland.sk/upl/wafap.pdfIn PDF document text
    • http://lica.plovdivweek.com/js/ckfinder/userfiles/files/bogodetizejidiruporok.pdfIn PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/fozubixibibun.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/naguzefunitutosonaxisefaj.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/tekubukojopire.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wafuwilitofevakiberabuzi.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/12485767025.pdfIn PDF document text
    • http://tythb.com/uploadfile/files/28152513525.pdfIn PDF document text
    • https://phucatgarment.com.vn/ckfinder/userfiles/files/53264905838.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=avakin+life+mod+androidPDF 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_off0000b584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB584 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD96 18504 bytes
SHA-256: 383e98e88aede26de89db4e2e2bedfdf0cd56b701806c796988e0b443058d525
font_02_sfnt_off0000fba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA2 10388 bytes
SHA-256: 6168a312dc0847fbdfec54712c8280bcf008ab4a90d2d91233c416142e847608
font_03_sfnt_off0001130e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1130E 1820 bytes
SHA-256: ef4c56b83544acc0eae329b123dcb13384a4443b8ee25b6b011fcec9f25c534c