Malicious PDF — malware analysis report

Static analysis result for SHA-256 d28474a3711afb27…

MALICIOUS

PDF

81.2 KB Created: 2021-07-03 03:52:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: a19999f50f26057ffd70997ccde6d3ef SHA-1: 21bc57d3abdd5b83ca4054891723ca0ad3f01187 SHA-256: d28474a3711afb27e4ce1bca649b2941a9276beb6f444a32ae986306795549ac
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised CMS upload storage. The presence of these links suggests an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://yuss.it/file/23895835798.pdf In PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/l3tkt3mojshcvohnt6v52njup4/nejepajasibilalamugufidi.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/61248662552.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a15a9a2a846---salut.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/05/files/210529105536.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d288bc3d3f---36070577655.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609960fa6a1a1---91352902821.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/92rt1qrgpqjagvhapf023omt8e/nasiwow.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/82151306381.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/pumikinezu.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de15e617918---571216297.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dfb2eb7795f---rexukerisalatidofelapuv.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160870fb36b3ce---benite.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/1dp1nugi4qgbuodktpegp5v6c7/41672119267.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160dab98c550b2---wusotuvunomedusawefo.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac52fa33a3---26642147090.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=the+subjunctive+examplesPDF 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_off0000daf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF6 10920 bytes
SHA-256: d9ac883f825675a5a992c5f8ac0d0db130be3accf48484dfc8ff0e21e2482343
font_01_sfnt_off0000f3d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D1 17488 bytes
SHA-256: ed10fb4f0d921db80e0764d982a210b849db0ccc9ac49333d734cfc162dca9f3
font_02_sfnt_off0001206f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1