Malicious PDF — malware analysis report

Static analysis result for SHA-256 a54a7f9a07da2c29…

MALICIOUS

PDF

82.1 KB Created: 2021-09-19 14:08:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c00fff836867d9e403011c5ed4186a74 SHA-1: 6571fc94c31d05cf0e6a3bd906530d5e3249285b SHA-256: a54a7f9a07da2c29de99d916af1f5df9d5ddc803adc8e229a65922791b310a44
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript and numerous external links, including one to an algorithmically generated URL, suggesting it's designed to lead users to malicious content or download further stages. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, further supporting a phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://archism.ru/uplcv?utm_term=video+player+in+android+studio PDF link annotation
    • https://ylwlgwadmin.ylwl.cn/upload/files/41339970612.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/dediluvixugi.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/33749264742.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/lutikerutekuju.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/repurumagifalaxapivutome.pdfIn PDF document text
    • http://baby-daycare.com/uploads/files/202109081932167087.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/82734615855.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/xobakajonatir.pdfIn PDF document text
    • http://eegbiofeedback-leszno.pl/userfiles/file/pomapimunubitoni.pdfIn PDF document text
    • https://xtremefitksa.com/ckfinder/userfiles/files/texuwiliwadigazixudi.pdfIn PDF document text
    • https://netlandschool.cl/files/19647499537.pdfIn PDF document text
    • http://pjteam.hu/uploads/susufupusatajelanagadajo.pdfIn PDF document text
    • http://mutitar.com/user_img/files/18890779617.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/42509503222.pdfIn PDF document text
    • http://parkingparts.com/Upfiles/file/favog.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/31711069311.pdfIn PDF document text
    • https://billard-hauri.ch/userfiles/file/nixusosurerisujemerasafow.pdfIn PDF document text
    • http://carshopm.com/js/upload/files/79006287124.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/9643511094.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/xosegiwegorosuji.pdfIn PDF document text
    • http://mayingiabao.com/upload/files/sivepitipozeko.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139a4ebdaa89---65938762648.pdfIn PDF document text
    • http://abwingstop.com/uploads/files/dijenivizetisela.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/60195515772.pdfIn PDF document text
    • http://bluecreator.biz/ckfinder/userfiles/files/89470658638.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_off0000dc18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC18 10568 bytes
SHA-256: 4f91ff9a8b2d556bce16a3c82383428b89881a48c6a9a7cfc3baffed8737aa20
font_01_sfnt_off0000f456.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF456 17424 bytes
SHA-256: 8f553ea31c666b689417efbdd71977b8f5d441283d1742526194a0ad631e7615
font_02_sfnt_off0001224e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1224E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1