Malicious PDF — malware analysis report

Static analysis result for SHA-256 51c99aa0d0764b9a…

MALICIOUS

PDF

85.8 KB Created: 2021-09-05 14:07:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 70706fbad9895bad60a242ad9abf6e7c SHA-1: 3d4e7d6116f125af6d4893e83e35f72b688db6fa SHA-256: 51c99aa0d0764b9ab438a1884a83fba4b0cfe14aebf1ac8d11905e41bf1e1107
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various websites, including those hosted on compromised CMS platforms. The primary attack pattern observed is the use of malicious links to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://yaqeen-eg.com/userfiles/file/petife.pdf
    • https://west-holding.com/userfiles/file/10336871699.pdf
    • https://aimhc.com/userfiles/file/ponumugako.pdf
    • http://ylgems.com/file_media/file_image/file/14266763498.pdf
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/5ba6b2d78340739e1e9e0366119d0805/rogavupokinodago.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/bc1df98ce008cf9610e47ca3457fee6e/vifovi.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/624507d76aa3238746a4fab777ca2f77/xolonikodopuzaxes.pdf
    • http://df-2.de/images/daten/file/bunipalitizamopariti.pdf
    • http://zuche0551.com/upload/file/31576419239.pdf
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/48626209041.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609dee27e1a83---29498879584.pdf
    • https://laser123.com/geektic/files/kakesikumasu.pdf
    • http://driver-jazda.pl/upload/file/mebufeze.pdf
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/legutuwidoritipimoza.pdf
    • https://kleinimmobiliere.lu/userfiles/files/tuxenu.pdf
    • http://beastyenergy.com/userfiles/file/82774311782.pdf
    • http://afghansolar.com/userfiles/file/jubak.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/c9fsjt57bu2idfg2p2iqd6nlf2/wawexojozavifiz.pdf
    • http://chinalabware.ru/d/files/13344562255.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/pghmdjd41ie2ltroutpc50f496/94442417629.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c024dc08c03---58069391423.pdf
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/70c83bbd8a7690f334a25002f3a55591/67272266979.pdf
    • https://drsubhashawale.com/ckfinder/userfiles/files/85246205105.pdf
    • http://fujiya-la.com/uploads/files/25528745926.pdf
    • http://pampa.be/uploads/userfiles/files/60377678812.pdf
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606feef142615---bedovatidimupamu.pdf
    • http://condosworld.com/abisol1/userfiles/files/fofexofipegomonoza.pdf
    • http://kerekesvillszer.hu/UserFiles/file/86666444302.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=small+scale+business+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_off0000ec63.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC63 16792 bytes
font_01_sfnt_off0001047a.bin
ef18d7541d3d7f3fc9f0dbb973f3f2d61663dff247b53528328b004b42eba244
pdf-font-stream PDF embedded font (sfnt) at offset 0x1047A 10780 bytes
font_02_sfnt_off00011cf8.bin
62d84d0cb3094a4a2c7cb41293ffafd83cbf768eee880c579c186f96ca8e5337
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF8 17208 bytes