Malicious PDF — malware analysis report

Static analysis result for SHA-256 398a4226442e389f…

MALICIOUS

PDF

67.5 KB Created: 2021-09-24 15:41:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3b82e51a858d2107ce250eebd7a10499 SHA-1: 864cdf98f8f4991ef04967ccda5f4b953848fc95 SHA-256: 398a4226442e389f30f1186db6c3e76a7f1ca2d7a1fd0ca4931334b9aec08f23
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure. It contains numerous links to external domains, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting an attempt to obscure the final destination. The document's structure, being image-heavy with minimal text, aligns with a common tactic of using a screenshot to mask clickable elements.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://calendarsunrooms.com/userfiles/files/24068653340.pdf In PDF document text
    • http://sartor.ru/upload/files/59620060231.pdfIn PDF document text
    • https://csn-alliance.com/data/files/karejigumupituzalulelivuf.pdfIn PDF document text
    • http://yonezawanet.jp/units/24250/zcycom/files/40189589573.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/59081907886.pdfIn PDF document text
    • http://sdes.in/uploads/dawuve.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2f3e67a6d---tuzebob.pdfIn PDF document text
    • http://sgpeo.pl/users/file/dubefiwiwuna.pdfIn PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/zetife.pdfIn PDF document text
    • http://esrafisek.com/images_upload/files/5876058106.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/liwisebu.pdfIn PDF document text
    • https://babycloud.ro/app/webroot/files/userfiles/files/9739882472.pdfIn PDF document text
    • https://sainaudit.mn/File/64769354349.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/pewovodofatazogog.pdfIn PDF document text
    • http://abwfinlay.com/uploads/files/19904554964.pdfIn PDF document text
    • http://agriturismoilnoceto.com/userfiles/files/88203323860.pdfIn PDF document text
    • https://sinarwaja.com/account/files/48262245983.pdfIn PDF document text
    • https://infypos.com/infyposcms/media/8376592418.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5e44d3400608c5d988ead9b0e797afc1/68444207874.pdfIn PDF document text
    • http://rjbmachinery.com/d/files/60850311144.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/161463107e28eb---65216098524.pdfIn PDF document text
    • http://techbico.vn/uploads/image/files/41933702695.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161458ad31f9aa---kujumovavisuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=wwe+2k+2021+downloadPDF 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_off0000ad5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD5A 14572 bytes
SHA-256: 982117086a6d9140b64d0a84625f260fd1fc71c34e512be22b4eb64d1702d667
font_01_sfnt_off0000d16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD16C 10248 bytes
SHA-256: 98b4558716b28eac5e03f20012f9c33b3fc79ffb19d0fa14376319e34d15942c
font_02_sfnt_off0000e8b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1