Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a71e36cc1377116…

MALICIOUS

PDF

87.4 KB Created: 2021-09-08 15:04:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6155773b9bba6f503e34ac8c7d545673 SHA-1: c4527567c73cee8a75a6506dc3484856414a0ed4 SHA-256: 0a71e36cc1377116a02fc2071661a0b6a6acb2409952c42116050e3435de2927
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple compromised websites, suggesting an attempt to distribute malicious content. The ML classifier strongly indicated maliciousness, and heuristics identified it as a link farm on disposable hosting. No scripts were extracted, but the presence of numerous URLs on compromised domains indicates a likely phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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 http://nakamurasangyou.jp/app/webroot/uploads/files/zurupa.pdf In PDF document text
    • http://erdbau-rauch.at/8712495670.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/nirijemogitudafadumenaxib.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/dovejufejevowosokobuf.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/161332cd4ad23d---79287087556.pdfIn PDF document text
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/lubobogefojipu.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/4hobtp09o39d5i0ib6ref2h817/49078570375.pdfIn PDF document text
    • http://dcbestwings.com/uploads/files/jowunusu.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/4901960954.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/bruut6mfho77qiohc12ki7r025/84940583393.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/99018981412.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/14128973138.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/xonafobajug.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/64597791149.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads/files/202109071535103839.pdfIn PDF document text
    • http://delfosventures.net/userfiles/files/20873852041.pdfIn PDF document text
    • http://casadiriposomarsala.it/userfiles/files/muwomudolijojekidapu.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/xofodaxadiloge.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/31804833469.pdfIn PDF document text
    • http://zkojicin.cz/userfiles/file/42773596025.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/kojixosonopomutaranoxudo.pdfIn PDF document text
    • http://grandwatergatehotel.com/upfile_hotel/files/zoxugesemu.pdfIn PDF document text
    • https://tectrongim.com/uploads/files/18363176565.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=peugeot+partner+tepee+owners+manualPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3F 10692 bytes
SHA-256: ddd9eb03d57ca7001356b5189de8d7f9c9d6d99715f4fb365102bf843bd6abbd
font_01_sfnt_off000105e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011df9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF9 18624 bytes
SHA-256: 51f3943266be14628700f4a93f0b4b41a0fcb56fc28d6b2887ef91fdfa54b589