Malicious PDF — malware analysis report

Static analysis result for SHA-256 903a5c052daa6ba4…

MALICIOUS

PDF

83.7 KB Created: 2021-07-03 16:46:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 22d27cb254eed8da70207875a3ce231d SHA-1: 95abb95d8ba543bb037f1f96fa67769ff83c1ba9 SHA-256: 903a5c052daa6ba4fe7633663a77aaf821f151d983d7a5d84c6c42c29770335f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS upload directories or disposable hosting, suggesting a phishing or malware distribution scheme. No scripts were extracted from this sample, but the structure and URL patterns are consistent with a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://soldearenales.com/galeria/files/63925235123.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9f03ee523---rijax.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc4210e17c---24918331366.pdf
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/df509b2cd07831ab4e553936ab78fea2/34145768734.pdf
    • http://jjinline.org/file_upload/file/dironuje.pdf
    • https://ildiko-szepsegszalon.hu/userfiles/file/66570893466.pdf
    • https://noddy.nu/images/file/sesudukadejagapesuze.pdf
    • http://cezanart.com/userfiles/file/mojexizudixepoderapefajig.pdf
    • http://degrossier.nl/uploads/file/vabilomazen.pdf
    • http://coreaad.com/DreamDataUpload/file/80834152981.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c4fa192a8cf---weralidefowunupajuxi.pdf
    • http://abaj.cz/UserFiles/File/kopizemorulupadozowe.pdf
    • http://krevue.cz/UserFiles/File/40048838876.pdf
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160715871822b5---bajigurolubobojopox.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160940c10540b9---vonirir.pdf
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/58374222464.pdf
    • http://haiphongcontest.com/images/files/29067004836.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8ef33aac6f---jepas.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/4f0b59cf70d74ed8890f8a62047dada5/2641173829.pdf
    • http://matstravel.ru/userfiles/file/44452140509.pdf
    • http://castrolmintabolt.hu/images/upload/file/lanavefebewinubonozeduxuj.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/e79458d1fdb9ae6e311ca10af72920ad/40573200187.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=speech+about+my+aim+in+life
    • 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_off0000e59b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE59B 16792 bytes
font_01_sfnt_off0000fdb2.bin
c74a7a61e56d897c59c18bc92b6d86f4ab291deeaf0880d81d6e88006c285e8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB2 10908 bytes
font_02_sfnt_off00011692.bin
45371e1de48ec337d24fe8b1d675df5d66aca198c80898620e8bea4b3e2fb7ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x11692 16688 bytes