Malicious PDF — malware analysis report

Static analysis result for SHA-256 15c55cceb87e45eb…

MALICIOUS

PDF

74.5 KB Created: 2021-09-14 12:36:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fbf6b9d0ffeb5103179d914d5603e396 SHA-1: a8a4d97a57e2acdbea63a2bf83c2ba09f83ea2b3 SHA-256: 15c55cceb87e45ebed74182a438d307db49dbe8baff509b018b001bc8e178e02
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many hosted on disposable domains or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple external links suggests an attempt to redirect the user to a malicious site, potentially exploiting a vulnerability or luring them into a phishing scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://zzfcw.com/file/fkimg/file/14517374692.pdf
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/36707631253.pdf
    • https://villatoscana-pi.it/userfiles/file/76789300487.pdf
    • http://sgyscom.com/upload_fck/file/2021-9-7/20210907003004766664.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/67582caf9c7336a3fb71b0372190dc86/bitokokuro.pdf
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/lazaperapifulawoj.pdf
    • http://www.childofafrica.org/media/userfiles/file/fopufepuwakax.pdf
    • http://dichvutot99.com/webroot/img/files/tabupodenagididi.pdf
    • http://runhouchem.com/upload/files/21482661528.pdf
    • http://robertfeinberglaw.com/images/edit_images/file/70886204399.pdf
    • https://dobski.pl/userfiles/file/sovonowomag.pdf
    • http://pusancard.com/userData/board/file/tofiker.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/3fc3302edcce58aecb3a1ecedc8588f3/tudewaruxefetugagako.pdf
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/77934cc2d235befd4ed7cbc004a5888c/pofujosisugupuwek.pdf
    • http://slovbau.sk/test/userfiles/file/wogirajadixetekuvixigeris.pdf
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/94457fd40cc90d31b9a9983944430784/77225779148.pdf
    • http://61kidsclub.com/userfiles/file/77877533327.pdf
    • http://www.mariabeckmann.com/fotos/uploads/files/bomin.pdf
    • http://fotografiafrancescosomma.com/userfiles/files/zuvubuxexog.pdf
    • https://minipowerpack.net/upload/files/46212640463.pdf
    • http://learnazia.com/fck/imagesfile/8801510173.pdf
    • http://hooleihomes.com/cms_images/file/lenul.pdf
    • http://ultrabeauty-ff.ru/userfiles/file/wenalerebitorulogi.pdf
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/14401701124.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=word+to+convert+excel
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c276.bin
f716dec4369eb17726f5a6ce0b7ccbef17af82332cb043b4355faa520accbe88
pdf-font-stream PDF embedded font (sfnt) at offset 0xC276 16768 bytes
font_01_sfnt_off0000ed5e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED5E 16792 bytes
font_02_sfnt_off00010575.bin
7bb85a0fd9f5a8576a765d470b796d831dbb0ad3abe5abf6678e027181ffed0c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10575 10100 bytes