Malicious PDF — malware analysis report

Static analysis result for SHA-256 0251b43ace9cabbb…

MALICIOUS

PDF

103.0 KB Created: 2021-07-01 15:41:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d4e44528b189c116b3f1d504f220398 SHA-1: 637bb047aaba5757e6f392c082aa8daf808a771c SHA-256: 0251b43ace9cabbb5b3ceec34984cc191eba1d770d0a2fc5c86fa0fdb23d4930
184 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress sites and potentially malicious content hosted on raw IP addresses. The presence of embedded URLs and the nature of the heuristics suggest the document is designed to trick users into downloading a second-stage payload, likely through a social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://yunnanyingxiang.com/ckfinder/userfiles/files/sifetukuradawokesaren.pdf
    • http://kotolantopeni.cz/file/meregazulewe.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4531ab265---pebolinugaxogof.pdf
    • http://augustaelectricalwork.com/editorData/file/38900053807.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/tbnj1oig8i27jqpmloh98m8dpv/76317245695.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607303fa82e80---sisogekukaredarozezix.pdf
    • http://bulk-supplies.com/userfiles/file/todijurufufevesurumazudaz.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e610345ede---bapokuforafozimalejidi.pdf
    • http://anhuicrew.com/upload_fck/file/2021-6-17/20210617202947175007.pdf
    • https://cloud-tutors.com/wp-content/plugins/super-forms/uploads/php/files/49de98d1534baa1ac17d435316eabebb/53434682641.pdf
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c022126fa7---dukakafatisunejulabekuta.pdf
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2f97df9f4---lapeluj.pdf
    • http://robalton.es/Albums/images/file///72706720004.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/fpl4t3ao1sh1t6c5b8bom2l73j/zefudezofirugavekus.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/9170888751b70dd825534df1542bcd3a/gimodofekereluxag.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a6db64973---gazosisipe.pdf
    • http://cravaluos.com/ckfinder/userfiles/files/xuzowowapinemifafovudoku.pdf
    • http://chongthamnguoc.vn/img/files/tenimizerezupasif.pdf
    • http://ligonfamilyreunion.org/clients/9/9a/9a44987365eba454cd9b2deda39aa7c0/File/silasuparovawokifas.pdf
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/23724721979.pdf
    • http://kadernictvo-svetlana.sk/editor_uploads/system/files/bibet.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/mamupemuwafobuzejozix.pdf
    • http://highendschmiede.de/highendfiles/file/dukaxosomewutapulowuwazi.pdf
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b061128aaca---luzemavizo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=does+tupac+have+a+child
    • 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_off000133d3.bin
b2a4e851220198e533d1352f7e593b1ea7ae8b58f1162e21ba0ed84aa400d97a
pdf-font-stream PDF embedded font (sfnt) at offset 0x133D3 10576 bytes
font_01_sfnt_off00014c23.bin
3cc012c988adc74abf96628497e32c2c9606dedd01effdcda301da0f0187cde1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C23 16352 bytes
font_02_sfnt_off0001769d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1769D 16792 bytes