Malicious PDF — malware analysis report

Static analysis result for SHA-256 1535c1ac69f41a86…

MALICIOUS

PDF

69.2 KB Created: 2021-09-10 06:53:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 399bcd774e2fb7035a6777360a8488bb SHA-1: bff63d2fc6c8065bdbc12301402a9d8afab2feac SHA-256: 1535c1ac69f41a868421fa673182b1db53e61dff82e7b54500b667d9022d66f7
156 Risk Score

Malware Insights

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

This PDF file exhibits characteristics of a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO spam. No scripts were extracted, but the presence of multiple external URIs suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://garglob.ru/uplcv?utm_term=shiny+pokemon+cheat+fire+red+emulator PDF link annotation
    • http://tz5168.com/uploadfile/image/2021/09/05/file/20210905_090538_182.pdfIn PDF document text
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/97213210622.pdfIn PDF document text
    • http://lonniestireandauto.com/nbloom/fckuploads/file/lazuwodijexuv.pdfIn PDF document text
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/1120595433.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/kemam.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/kizufemubo.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132190aede33---dugekew.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/35952582708.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/maluzumemolag.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/lufolojefojixidifoxenog.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/161397fd2a0ad8---puparenitomewebapiniji.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/89669898220.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/24414687351.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/b10499ff97987d986077f3452fda7ad4/943176808.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/wonevajijuligesurixamarat.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/kidumurejudur.pdfIn PDF document text
    • http://www.serge-valentin.net/ckfinder/userfiles/files/luvepusixal.pdfIn PDF document text
    • https://promptcorporate.com/ckeditor/ckfinder/userfiles/files/88458792161.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/22043816923.pdfIn PDF document text
    • http://accronline.com/userfiles/file/20916665506.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/66998636702.pdfIn PDF document text
    • http://the-bom.kr/upfile/files/9760263142.pdfIn PDF document text
    • 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_off0000aedf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEDF 11100 bytes
SHA-256: b9f62909d5dd56e32606273c3ea9daef678b5e4c3c97e1eb0d68f554309dd418
font_01_sfnt_off0000c895.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC895 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e0a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A7 14972 bytes
SHA-256: ee7caa5caa00d5e69d5310dd8e4a901422bc6aa8beb065ec9d282bf35d81fccb