Malicious PDF — malware analysis report

Static analysis result for SHA-256 a26ecf6e5d0c5ef9…

MALICIOUS

PDF

83.3 KB Created: 2021-09-16 03:50:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d5e3563b8eb99126d97f6b203d2ec70e SHA-1: dbf0cf473f3e441bdcf608166265572402a6549c SHA-256: a26ecf6e5d0c5ef9e29642a2c20158fc83ffa53d9292cb1c052dd43499df48ee
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious links, which are designed to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f55b928a9---wirekipatopilifozok.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6963d04d7---degawotefukupiwulubudoruf.pdf
    • http://vizesblokk.hu/files/file/41925526448.pdf
    • https://asiapharma.la/files/files/ritoximevanuturafo.pdf
    • http://thunderstar.cn/userfiles/file/20210910075501592764506.pdf
    • https://lixtech.com.tw/ckfinder/ckfiles/files/39650106055.pdf
    • https://banderlogclub.ru/Files/file/pakinorokejurogel.pdf
    • http://fullcolorspandoeken.nl/userfiles/file/43469541142.pdf
    • http://toyotaquangninh.org/data/dulieu/files/taburukujafam.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16140390711cb3---98045373942.pdf
    • https://numen-wow.com/userfiles/cloud/files/28947420965.pdf
    • https://www.zolmedis.lt/ckfinder/userfiles/files/36513392224.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134c44f79fe1---gamuwi.pdf
    • http://pattarasawat.com/ckfinder/userfiles/files/vogovada.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137f0cd4d99a---xelosotuwogogukonuv.pdf
    • https://dichvuketoansg.com/luutru/files/5665348266.pdf
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210903_4DFE0B50611547F5.pdf
    • http://thongthien.vn/upload/files/18326568368.pdf
    • http://fabriquetextil.com/js/new/fckeditor/userfiles/file/94208664448.pdf
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/xobananam.pdf
    • https://vietucmould.com/img-vietuc/files/dikek.pdf
    • http://ferrocom-spb.ru/userfiles/files/mopubelowowulemokufat.pdf
    • http://dolinakrzeptowa.pl/public/upload/ckfinder/userfiles/files/wanuro.pdf
    • http://whkmradio.com/userfiles/file/15186814043.pdf
    • http://kammed.com/userfiles/file/85702048647.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=how+to+add+a+device+to+find+my+device+android
    • 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_off0000e08c.bin
e6daec21c2491b0ac7b166512bad13683adb6f3f0bb74013e1e8c9c49b075505
pdf-font-stream PDF embedded font (sfnt) at offset 0xE08C 17764 bytes
font_01_sfnt_off00010ec9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC9 16792 bytes
font_02_sfnt_off000126e0.bin
daee67f28751254ca212df2d40d0815d4047ef21338573e4d9858fe1f2d41a04
pdf-font-stream PDF embedded font (sfnt) at offset 0x126E0 10680 bytes