Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc5d1cf7c55d9b96…

MALICIOUS

PDF

82.4 KB Created: 2021-09-17 22:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 59e08f32e7ab9d61fe0ae6bf33792ba1 SHA-1: ec1f2781817cc6a060eab56aa022fb43e07b6884 SHA-256: dc5d1cf7c55d9b96c46b7edb2d615b7e0ff84ea1c033e9677b60df5f6d354af6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://irlanc.ru/uplcv?utm_term=composite+numbers+meaning+in+telugu
    • http://xn-----6kcaheblih5ab0a6afqbzoqe.xn--p1ai/ckfinder/userfiles/files/fokovarijalofakelediwu.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1613a024018439---tekemijofewofexitu.pdf
    • http://naplesredeals.com/userfiles/files/neluzobafapabararegine.pdf
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/fn43798mg14sgmoebolcmoem7j/niwonefanokobit.pdf
    • http://findingthegrey.com/userfiles/file/vetoripovuwonenijawumiz.pdf
    • https://altonika.pro/files/fck/file/5959755571.pdf
    • https://iword.de/userfiles/file/dorikit.pdf
    • http://thebookmarkcafe.com/uploads/files/dajepodekitixinemi.pdf
    • http://asztalosweb.hu/userfiles/file/25042841505.pdf
    • http://jar-ted.pl/file/1466561823.pdf
    • https://dodatnagarancija.com/userfiles/file/luxujudivukidafo.pdf
    • http://graviroz.hu/ckfinder/userfiles/files/83855461623.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161319252badcf---zezojatuvebovuposepejak.pdf
    • http://congtyvima.com/images/Download/dafirotenevenelewutezaru.pdf
    • http://investin-khj.ir/ckfinder/userfiles/files/datexonazo.pdf
    • http://waetsukai.jp/system/ckfinder/userfiles/files/65213762505.pdf
    • http://fukaofoods.tw/uploads/files/202109170719461011.pdf
    • http://drapikowski.pl/uploaded/fck_files/file/vovefefizuwoxuzejugexizaj.pdf
    • http://crm333.com/documentos/file/99031056105.pdf
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/62890703482.pdf
    • http://cualuoiskydoor.com/webroot/img/files/60374103131.pdf
    • http://moristas.com/userfiles/files/32351231772.pdf
    • http://mega-gold.com/userfiles/files/nipozitafosatowuxawoduzod.pdf
    • http://opuspoint.com/ckfinder/userfiles/files/17329432383.pdf
    • https://harley.dataroom.tw/upload/files/58671670248.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_off0000d574.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD574 16792 bytes
font_01_sfnt_off0000ed86.bin
2fc25eb7d3fea96267ceb6cae7e21726f54acb845c8aa5c1ece53dfaf15efeeb
pdf-font-stream PDF embedded font (sfnt) at offset 0xED86 20172 bytes
font_02_sfnt_off00012293.bin
e5813c492ebfc13c3b1fbd0ae5f708bdef6042e2e42d53b3483dbea1e87c0a14
pdf-font-stream PDF embedded font (sfnt) at offset 0x12293 10864 bytes