Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c54ab4f17c6ad77…

MALICIOUS

PDF

84.3 KB Created: 2021-09-07 08:25:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b5187ed8aaa9477015726a214382e665 SHA-1: 95a36d4b72db2cbc75516928ff36e8a68dee4509 SHA-256: 5c54ab4f17c6ad7735358aa14e0633073d70e041f76275d7832f2878169a4219
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://xiangzhuan.tw/upload/files/58354010701.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/892abe51e384067e25f7286c41aff5c1/59243465865.pdf
    • http://acevina.com/webroot/img/files/77760296735.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/beff7ee694a0a59820f3262faeef7c8b/wofatumevijekazixagoritez.pdf
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/busorixotelogamigugajek.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160759646eb99d---8722726923.pdf
    • http://heyumpnd.com/userfiles/file///manevonexunolagiwadawibu.pdf
    • http://www.polni.si/Images/files/50633361055.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080facc47183---mepiletofabewakepep.pdf
    • http://carscaso.com/js/upload/files/sogojuliregum.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607009cdcd3b5---28459788651.pdf
    • http://lyzebrno.cz/userfiles/file/87107890827.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16083729816caa---gunub.pdf
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ac6af1390668899e7e82c8dafef4c5e6/71529633739.pdf
    • http://hz-kontejnery.cz/ckfinder/userfiles/files/vapajetepurewe.pdf
    • http://kabelkyaobuv.sk/editor_uploads/files/72851454556.pdf
    • http://briquettemachinery.com/d/files/zoxufebabumoxogulefaxe.pdf
    • http://barudan.hk/UploadFile/file/20210630070454988.pdf
    • http://toroisg.com/public/images/files/virunet.pdf
    • http://hosungtour.com/FileData/ckfinder/files/20210722_60B3EAAE1D69630C.pdf
    • http://faxik.online/ckfinder/userfiles/files/90284019889.pdf
    • http://alacarte-design.de/userfiles/file/73893812157.pdf
    • http://gjbbang.com/userData/board/file/bixijagole.pdf
    • http://skazka76.ru/pic/userfile/25394279466.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=fitbit+charge+hr+3+manual
    • 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_off0000e68f.bin
86170c428905d6103d53d0c9605ed167aa5f931ecff6192ac484f6eb737d9a50
pdf-font-stream PDF embedded font (sfnt) at offset 0xE68F 10776 bytes
font_01_sfnt_off0000ff35.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF35 16792 bytes
font_02_sfnt_off00011747.bin
cc1fd8cda64c26b7ab6628bf4cb435e0653fc92662fed0f443ccc6b811722a4d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11747 17344 bytes