Malicious PDF — malware analysis report

Static analysis result for SHA-256 99a9318a0bf2db1d…

MALICIOUS

PDF

82.5 KB Created: 2021-09-19 19:03:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: bcd7c02b19c6eb3c9341851def4d887d SHA-1: a6ef5e91440f9c3582535b5b2836480e48283110 SHA-256: 99a9318a0bf2db1d6c44939457b31bcb61a2b6722687e37b2caa8f018a4273e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple domains, some of which appear to be compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery via these links. No scripts were extracted, but the heuristic findings and numerous URLs suggest a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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 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://crysiq.ru/uplcv?utm_term=lord+of+the+rings+wallpaper+android PDF link annotation
    • http://vipacademy.org/userfiles/file/97834464688.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/66429716774.pdfIn PDF document text
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/saritopagiwevozusatuk.pdfIn PDF document text
    • https://nezrenpin.com/calisma2/files/uploads/65775591101.pdfIn PDF document text
    • http://resumesfromabove.com/userfiles/file/vejimom.pdfIn PDF document text
    • http://whygzy.com/Media/Uploads/files/zezawuvokis.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/5622628211.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/1c032baeaed6606a23e7f308eb86a6ba/37292587414.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/38843726355.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/jilegezazu.pdfIn PDF document text
    • https://jdsliquorlocker.com/nbloom/fckuploads/file/35962541236.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f31c13d838---24245594592.pdfIn PDF document text
    • http://xn--80aer5aza.xn--c1acndkmcarx.xn--p1ai/ckfinder/userfiles/files/lubusenitag.pdfIn PDF document text
    • http://carrozzeriabosini.net/userfiles/files/85808599814.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/kipowulodafanubaxa.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/vebubivopigetuwokuzer.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/40514207844.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16141f01c2d2a4---lofasibekivamitorutesu.pdfIn PDF document text
    • http://hangquangauto.com/files/14577307619.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/jemixepuwuxikirozulok.pdfIn PDF document text
    • http://kidneytracker.com/ckfinder/userfiles/files/bitajoxiwebuxarog.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_off0000dcb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB6 18180 bytes
SHA-256: 69719328f046e212496d8b9da03e463506099fccd7036e8279d250a3ba0fe372
font_01_sfnt_off00010bac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C3 10820 bytes
SHA-256: baa4e6045728044d5b17ab5648dfa811d1d3a8c84e5abb443b41d5cfb6bdb6c3