Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ba0755720522559…

MALICIOUS

PDF

100.8 KB Created: 2021-07-02 07:25:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28b34a0fc366bed93010997a449435dc SHA-1: 5cbd297151f6efe349700f1fbe7bf675a0c360ef SHA-256: 7ba075572052255982286d72f168246fccd69fc0871828322a3075c341f3eb26
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload storage and disposable hosting. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous external links suggests an attempt to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 http://abnicum.com/files/file/gajapovoweg.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/gt16ddmn4mpcc4gr952vj86sla/zenuwokomo.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd386baf0ce---60813929918.pdf
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d67353adfe---sepijewoxamik.pdf
    • https://allmassage.net/upload/file/20210515215243.pdf
    • http://habitat3.eu/userfiles/files/legopetedonadigenotag.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/7424a6ccd3e456175a38a492c09a05f8/lasosotabobijomikeko.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2708adbfb---zumunazolifu.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/6d61e1577c2628ecc46b272088ef2a51/toxexudizumo.pdf
    • http://gayaarchi.com/userfiles/file/20210611111132.pdf
    • http://alituncer.com/userfiles/file/25668976003.pdf
    • http://lycee-elm.org/userfiles/file/bunerozemegi.pdf
    • https://taechoclub.com/FileData/ckfinder/files/20210609_A974EF99AB29A42E.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bc068be0bd---26458865327.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b73ad63708---20070348524.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/30d6dd9915f5a52da4467a3771add32e/52415497003.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad7ba3f244---zukojuxemed.pdf
    • http://ldbell1965.net/clients/85689/File/femavepimazana.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b46150b2554---furutitikojozuladodaxe.pdf
    • http://www.chatanakonci.cz/userfiles/file/38575673432.pdf
    • http://bpsstudio.hu/uploads/nejujowogazuwiwami.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/592b11918f7bb507644b100528478632/riwujupumufepopovuni.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/cff48902f6bdb378f325bad367818d27/zuruxu.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160911b6446c6c---12947346799.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=affinity+pull+down+assay
    • 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_off00012602.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12602 16792 bytes
font_01_sfnt_off00013e19.bin
0faf722b2eb7c90fb07a1d5d9100634681a7bf294d485dc2d85c606b0ea71780
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E19 10540 bytes
font_02_sfnt_off00015649.bin
f70f4a6e3eafed638b9607a64827a5dd965684acce26f6217ee898dd7607ca19
pdf-font-stream PDF embedded font (sfnt) at offset 0x15649 18312 bytes