Malicious PDF — malware analysis report

Static analysis result for SHA-256 a673fcb1eb7e30be…

MALICIOUS

PDF

87.3 KB Created: 2021-09-09 17:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1012850863baf0c798a62fcb5c3c3bcf SHA-1: cf517fd2893a0ba30c04e36cbb7b805d4d635cbb SHA-256: a673fcb1eb7e30be3e1ae32e313a8c1168be2517a13f98706a820afd74c213d7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are hosted on disposable domains and utilize UTM parameters, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attack pattern involving redirecting users to potentially malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://chcial.ru/uplcv?utm_term=socialproof+free+like+instagram PDF link annotation
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/ahfqen9ice1aamemo8jskeoqu3/napasuxuregegivaz.pdfIn PDF document text
    • http://njboyuanchem.com/upload/files/ponemiditufunewetuxup.pdfIn PDF document text
    • https://mimpishio.com/contents/files/44952022934.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161365e1965791---favuroranebasifa.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/4604184419.pdfIn PDF document text
    • https://ww150003.linebot.net/upfile/files/20210908195826.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/jelotojibodobisara.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/68849394087.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/siduzipadasizaf.pdfIn PDF document text
    • http://sampoernastrategic.com/uploads/image/files/70963345912.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/sutiv.pdfIn PDF document text
    • http://jornalespacoaberto.com/app/webroot/datafiles/editor/files/damojedogil.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/wijefenizonemenoguto.pdfIn PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/gatakozaf.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/13924816526.pdfIn PDF document text
    • http://guchen.ru/d/files/56673313913.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/161318e710c860---8909064782.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/menosokadununo.pdfIn PDF document text
    • https://t2sc.me/userfiles/seremosovururafawi.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/tonezowigigutumulovisi.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/dazizoj.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/kudekatoxujateb.pdfIn PDF document text
    • https://atiksigorta.com/files/87065558208.pdfIn PDF document text
    • http://vip-cond.ru/userfiles/file/wovana.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_off0000ef64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10776 17932 bytes
SHA-256: ab57176de2931d351fe72a72d91a8c8412a5f03b6d0b1ce40710ec99aa2d3f14
font_02_sfnt_off000135b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135B5 10992 bytes
SHA-256: 96f2a489d7a555ff52b22d3f602d6ea86af88a2056f7def977406436313b12ae